Sofia has been an area of human habitation since at least 7000 BC. Being Bulgaria's primate city, Sofia is a hometown of many of the major local universities, cultural institutions and commercial companies. Sofia is one of the top 10 best places for start-up business in the world, especially in information technologies. Sofia was Europe's most affordable capital to visit in 2013.
For the longest time the city possessed a Thracian name, derived from the tribe Serdi, who were either of Thracian, Celtic, or mixed Thracian-Celtic origin. The Serdi and the name of emperor Marcus Ulpius Traianus (53 – 117 AD) prompted the Romans to give the city the combinative name of Ulpia Serdica; Ulpia is derived from an Umbrian cognate of the Latin word lupus, meaning "wolf." It seems that the first written mention of Serdica was made during his reign and the last mention was in the 19th century in a Bulgarian text (Сардакіи, Sardaki). During the Romans civitas Serdenisium was mentioned the "brightest city of the Serdi" in official inscriptions. The city was major throughout the past ever since Antiquity, when Roman emperor Constantine the Great referred to it as "my Rome", and it nearly became his capital.
Other names given to Sofia, such as Serdonpolis (Σερδών πόλις, "City of the Serdi" in Greek) and Triaditza (Τριάδιτζα, "Trinity" in Greek), were mentioned by Byzantine Greek sources or coins. The Slavic name Sredets (Срѣдецъ), which is related to "middle" (среда, "sreda") and to the city's earliest name, first appeared on paper in an 11th-century text. The city was called Atralissa by the Arab traveller Idrisi and Strelisa, Stralitsa or Stralitsion by the Crusaders.
The name Sofia comes from the Saint Sofia Church, as opposed to the prevailing Slavic etymology among Bulgarian cities and towns. It is ultimately derived from the Egyptian Kemetic word sbÅ (𓋴𓃀𓄿𓇼𓇳), meaning "star, door, teaching and wisdom" and attested first in the 20th century BC in the tomb of Intef I. This was a tradition of collection of wise literature, shared between Mediterranean cultures, which was called sophia (σοφία) in Greek. The earliest works where this latest name is registered are the duplicate of the Gospel of Serdica, in a dialogue between two salesmen from Dubrovnik around 1359, in the 14th-century Vitosha Charter of Bulgarian tsar Ivan Shishman and in a Ragusan merchant's notes of 1376. In these documents the city is called Sofia, but at the same time the region and the city's inhabitants are still called Sredecheski (срѣдечьскои, "of Sredets"), which continued until the 20th century. The city became somehow popular to the Ottomans by the name Sofya (صوفيه). In 1879 there was a dispute about what the name of the new Bulgarian capital should be, when the citizens created a committee of famous people, insisting for the Slavic name. Gradually, a compromise arose, officialisation of Sofia for the nationwide institutions, while legitimating the title Sredets for the administrative and church institutions, before the latter was abandoned through the years.
The city's name is pronounced by Bulgarians with a stress on the 'o', in contrast with the tendency of foreigners to place the stress on 'i'. The female given name "Sofia" is pronounced by Bulgarians with a stress on the 'i'.
Sofia City Province has an area of 1344 km2. Sofia's development as a significant settlement owes much to its central position in the Balkans. It is situated in western Bulgaria, at the northern foot of the Vitosha mountain, in the Sofia Valley that is surrounded by the Balkan mountains to the north. The valley has an average altitude of 550 metres (1,800 ft). Unlike most European capitals, Sofia does not have any large rivers or bridges, but is surrounded by comparatively high mountains on all sides. Three mountain passes lead to the city, which have been key roads since antiquity, Vitosha being the watershed between Black and Aegean Seas. A number of low rivers cross the city, including the Vladayska and the Perlovska. The Iskar River in its upper course flows near eastern Sofia. The city is known for its 49 mineral and thermal springs. Artificial and dam lakes were built in the twentieth century. While the 1818 and 1858 earthquakes were of very high intensity and were destructive, the 2012 Pernik earthquake occurred west of Sofia with a moment magnitude of 5.6 and a much lower Mercalli intensity of VI (Strong). The 2014 Aegean Sea earthquake was also noticed in the city.
Air pollution is a problem in Sofia due to its location in the Sofia valley, which is surrounded by mountains that reduce the ability of the air to self-clean. The air is polluted mostly by particulate matters and nitrogen oxides. Sofia has the most polluted air of any capital in the EU.
Sofia has a humid continental climate (Köppen climate classification Dfb) with an average annual temperature of 10.6 °C (51.1 °F).
Winters are cold and snowy. In the coldest days temperatures can drop below −15 °C (5 °F), most notably in January. The lowest recorded temperature is −28.3 °C (−19 °F) (24 January 1942). Fog is not unusual, especially in the beginning of the season. On average, Sofia receives a total snowfall of 97 cm (38.2 in) and 58 days with snow cover. The snowiest recorded winter was 1995/1996 with a total snowfall of 171 cm (67.3 in). The record snow depth is 57 cm (22.4 in) (25 December 2001).
Summers are warm and sunny. In summer, the city generally remains slightly cooler than other parts of Bulgaria, due to its higher altitude. However, the city is also subjected to heat waves with high temperatures reaching or exceeding 35 °C (95 °F) in the hottest days, particularly in July and August. The highest recorded temperature is 41 °C (106 °F) (5 July 2000 and 24 July 2007). The hottest recorded summer was in 2012 with a daily average July temperature of 24.8 °C (76.6 °F).
Springs and autumns in Sofia are relatively short with variable and dynamic weather, intensive storms, sudden cold or heat waves.
The city receives an average precipitation of 581.8 mm (22.91 in) a year, reaching its peak in late spring and early summer when thunderstorms are common. The wettest recorded year was 2014 with a total precipitation of 1,066.6 mm (41.99 in).
Sofia has been an area of continuous human habitation since at least the 8th millennium BC, but others have inhabited the area 30,000 years ago. The city has a history of nearly 7000 years and it is the second oldest city in Europe according to the city's official website and other sources, though the meaning of the claim is unclear as in the world there were hardly any cities at the time. In the context, certainly the neolithic village in Slatina, dating to the 5th–6th millennium BC, is described. However, the motto of the city is "grows, but does not age". Remains from another neolithic settlement around the National Art Gallery are traced to the 3rd–4th millennium BC, which has been the traditional centre of the city ever since and is not changed today. The earliest tribes who settled were the Thracians. In 1400 – 1300 BC. Sofia's area was populated by the Thracian tribe of Tilataei. After the Celtic invasion in 3rd century BC Tilataei were conquered by the Celtic tribe of Serdi. The Celts were assimilated by the local Thracian population during the late Hellenistic period in 2nd – 1st century BC. According to some sources, it got first an official mention in the 7th/8th century BC when the Serdi (Sardi) as a Thracian tribe established a settlement. Other sources suppose that the Serdi's Celtic origin is convincingly evidenced through linguistic and archaeological clues but that their presence is not evidenced before the 1st century BC, whereas others assume their mixed Thracian-Celtic origin or relation to the Sards. The earliest evidence of Celtic presence in the Sofia area (Pernik) can be from the 3rd century BC. Some clues lead to the conclusion that the area of the settlement was between TZUM, Sheraton Hotel and the Presidency. In the 500s BC, the area became part of a Thracian state union, called the Odrysian kingdom, when another Thracian tribe appeared in the town, the Odrysses. For a short period the Thracian rule was possibly interrupted by the Achaemenid Empire. In 339 BC Philip II of Macedon destroyed and ravaged the town which was its first time.
Around BC 29, Serdica was conquered by the Romans, gradually becoming the most important Roman city of the region. It became a municipium during the reign of Emperor Trajan (98–117). Serdica expanded, as turrets, protective walls, public baths, administrative and cult buildings, a civic basilica, an amphitheatre, a circus, the City Council (Boulé), a large forum, a big circus (theatre), etc. were built. Serdica was a significant midway city on the Roman road Via Militaris, connecting Singidunum and Byzantium. In the 3rd century, it became the capital of Dacia Aureliana, and when Emperor Diocletian divided the province of Dacia Aureliana into Dacia Ripensis (at the banks of the Danube) and Dacia Mediterranea, Serdica became the capital of the latter. Serdica's citizens of Thracian descent were referred to as Illyrians probably because it was at some time the capital of Eastern Illyria (Second Illyria). For future emperors Serdica was their residence form where they ruled Rome.
Roman emperors Aurelian (215–275) and Galerius (260–311) were from Serdica. The city subsequently expanded for a century and a half, it became a significant political and economical centre, more so — it became one of the first Roman cities where Christianity was recognised as an official religion (under Galerius). The Edict of Toleration by Galerius was issued in 311 in Serdica by the Roman emperor Galerius, officially ending the Diocletianic persecution of Christianity. The Edict implicitly granted Christianity the status of "religio licita", a worship recognised and accepted by the Roman Empire. It was the first edict legalising Christianity, preceding the Edict of Milan by two years. For Constantine the Great it was 'Sardica mea Roma est' (Serdica is my Rome). He considered making Serdica the capital of the Byzantine Empire instead of Constantinople. which was already not dissimilar to a tetrarchic capital of the Roman Empire. In 343 AD, the Council of Sardica was held in the city, in a church located where the current 6th century Church of Saint Sophia was later built.
The city was destroyed in the 447 invasion of the Huns and the city laid in ruins for a century It was rebuilt by Byzantine Emperor Justinian I. During the reign of Justinian it flourished, being surrounded with great fortress walls whose remnants can still be seen today.
The city first became part of the First Bulgarian Empire during the reign of Khan Krum in 809, after a long siege. Afterwаrds, it grew into an important fortress and administrative centre when Khan Omurtag made it a centre of Sredets province (Sredetski komitat, Средецки комитат). After the conquest of the Bulgarian capital Preslav by Sviatoslav I of Kiev and John I Tzimiskes' armies in 970–971, the Bulgarian Patriarch Damyan chose Sofia for his seat in the next year and the capital of Bulgaria was first moved to Sredets. In the second half of 10th century the city was ruled by Komit Nikola and his sons, popular as "Komitopuli". One of them is Samuil, who became an Emperor of Bulgaria in 997. After a number of unsuccessful sieges, the city fell to the Byzantine Empire in 1018, but once again was incorporated into the restored Bulgarian Empire at the time of Tsar Ivan Asen I.
In 1382, Sofia was seized by the Ottoman Empire in the course of the Bulgarian-Ottoman Wars after a long siege. Around 1393 it became the seat of newly established Sanjak of Sofia.
The city was occupied by Hungarian forces for a short time in 1443. After the failed crusade of Władysław III of Poland in 1443 towards Sofia, the city's Christian elite was annihilated and the city became the capital of the Ottoman province (beylerbeylik) of Rumelia for more than four centuries. In the 16th century, Sofia's urban layout and appearance began to exhibit a clear Ottoman style.
There were fountains, hamams (bathhouses), prominent churches such as Saint Sofia were converted into mosques and in total there were 11 big and over 100 small mosques by the 17th century, of which only the Banya Bashi remains as a mosque today. During that time the town had a population of around 7,000.
The town was seized for several weeks by Bulgarian hajduks in 1599. In 1610 the Vatican established the See of Sofia for Catholics of Rumelia, which existed until 1715 when most Catholics had emigrated. The town was the centre of Sofia Eyalet (1826–1864). Nedelya Petkova created the first Bulgarian school for women in the city. The Ottomans hanged in Sofia the most honoured Bulgarian revolutionary of all time, Vasil Levski in 1873.
During the Russo-Turkish War of 1877–78, Suleiman Pasha threatened to burn the city, until the foreign councils Leandre Legay, Vito Positano, Rabbi Gabriel Almosnino and Josef Valdhart interceded for the city to be saved. However this saving did not apply to the Bulgarian citizens who faced executions. Sofia was liberated (see Battle of Sofia) from Ottoman rule by Russian forces under Gen. Iosif Gurko on 4 January 1878. It was proposed as a capital by Marin Drinov and was accepted as such on 3 April 1879. By the time of its liberation the population of the city was 11,649.
Most mosques in Sofia were destroyed in that war, seven of them destroyed in one night in December 1878 when a thunderstorm masked the noise of the explosions arranged by Russian military engineers.
For a few decades after the liberation, Sofia experienced large population growth, mainly by migration from other regions of the Principality (Kingdom since 1908) of Bulgaria, and from the still Ottoman Macedonia and Thrace.
In 1900 the first electric lightbulb in the city was turned on.
In the Second Balkan War, Bulgaria was fighting alone practically all of its neighbouring countries. When the Romanian Army entered Vrazhdebna in 1913, then a village seven miles (11 kilometres) from Sofia, now a suburb, this prompted the Tsardom of Bulgaria to capitulate.
In 1925 a terrorist act of ultra-leftists failed their attempted assassination of the king but resulted in the destruction of the Saint Nedelya Church and many victims.
During the Second World War, Bulgaria declared war on the US and UK on 13 December 1941 and in late 1943 and early 1944 the US and UK Air forces conducted bombings over Sofia. As a consequence of the bombings around 2000 people were killed and thousands of buildings were destroyed or damaged including the Capital Library and thousands of books. In 1944 Sofia and the rest of Bulgaria was occupied by the Soviet Red Army and within days of the Soviet invasion Bulgaria declared war on Nazi Germany.
In 1945 the communist Fatherland Front took power and executed several thousand people. The transformations of Bulgaria into the People's Republic of Bulgaria in 1946 and into the Republic of Bulgaria in 1990 marked significant changes in the city's appearance. The population of Sofia expanded rapidly due to migration from rural regions. New residential areas were built in the outskirts of the city, like Druzhba, Mladost and Lyulin.
During the Communist Party rule a number of the city's most emblematic streets and squares were renamed for ideological reasons, with the original names restored after 1989.
The Georgi Dimitrov Mausoleum, where Dimitrov's body had been preserved in a similar way to the Lenin mausoleum, was demolished in 1999.
Sofia as a capital is the location of all Bulgarian state authorities – executive, legislative, judiciary, the headquarters of all parties and the delegation of the European Commission. This includes the Parliament, the Presidency, the Council of Ministers and all the ministries, supreme courts and the Constitutional Court of Bulgaria.
Sofia Municipality is identical to Sofia City Province, which is distinct from Sofia Province, which surrounds but does not include the capital itself. Besides the city proper, the 24 districts of Sofia Municipality encompass three other towns and 34 villages. Districts and settlements have their own governor who is elected in a popular election. The assembly members are chosen every four years. The common head of Sofia Municipality and all the 38 settlements is the mayor of Sofia. The current mayor Yordanka Fandakova is serving a third consecutive term, having won the 2015 election at first round with 238,500 votes, or 60.2% of the vote, when Reformist Bloc opponent Vili Lilkov was second with 9.6%; the turnout was 41.25%. Some party leaders claimed that ballots were falsified and called for annulment of the election. A precedent happened, due to the suspicion, as a preventative action between 300 and 5000 people and counters had been locked inside Arena Armeets against their will for two days, following which the director of the Electoral Commission of Sofia resigned at the request of Prime Minister Boyko Borissov.
The number one problem that mayor Yordanka Fandakova acknowledges and is working on is the street dogs in Sofia. Although according to officials Sofia hosts 6600 street dogs currently, unofficially there at between 35,000 and 70,000 stray dogs. They have become part of urban life in Sofia, but the problem spotted into light after a pack mauled a prominent Columbia University professor to death in 2012, who was the president of the Wall Street Investment Bank and worked for the US Department of State, the United Nations and the World Bank.
With a murder rate of 1.8/per 100.000 people (as of 2009) Sofia is a quite safe capital city. Nevertheless, in the 21st century, crimes, including Bulgarian mafia killings, caused problems in the city, where authorities had difficulties convicting the actors, which had caused the European Commission to warn the Bulgarian government that the country would not be able to join the EU unless it curbed crime (Bulgaria eventually joined in 2007). Many of the most severe crimes are contract killings connected to the organised crime, but these had dropped in recent years after several arrests of gang members. Corruption in Bulgaria also affects Sofia's authorities. According to the director of Sofia District Police Directorate the largest share of the crimes are thefts, making up 62.4% of all crimes in the capital city. Increasing are frauds, drug-related crimes, petty theft and vandalism. According to a survey, almost a third of Sofia's residents say that they never feel safe in the Bulgarian capital, while 20% always feel safe. As of 2015 the consumer-reported perceived crime risk on the Numbeo database was "high" for theft and vandalism and "low" for violent crimes; safety while walking during daylight was rated "very high", and "moderate" during the night. With 1,600 prisoners the incarceration rate is above 0.1%; however, roughly 70% of all prisoners are part of the Romani minority.
Sofia concentrates the majority of Bulgaria's leading performing arts troupes. Theatre is by far the most popular form of performing art, and theatrical venues are among the most visited, second only to cinemas. The oldest such institution is the Ivan Vazov National Theatre, which performs mainly classical plays and is situated in the very centre of the city.
The National Opera and Ballet of Bulgaria is a combined opera and ballet collective, established in 1891. However, it did not begin performances on a regular basis until 1909. Some of Bulgaria's most famous operatic singers, such as Nicolai Ghiaurov and Ghena Dimitrova, have made their first appearances on the stage of the National Opera and Ballet. The National Palace of Culture regularly hold classical concerts. Bulgaria's largest art museums are located in the central areas of the city. Two emblematic galleries in Sofia – the National Art Gallery and the National Gallery for Foreign Art united their collections in a new structure. Seven Ministers of Culture have worked on this project over the years. The project gathered under one roof a host of Bulgarian, European, American, Asian and African works of art. Nearly two thousand works created by artists from Bulgaria and abroad are on display in twenty eight exhibition halls. Its collections encompass diverse cultural items such as Ashanti Empire sculptures, Buddhist art, Dutch Golden Age painting, works by Albrecht Dürer, Jean-Baptiste Greuze and Auguste Rodin, among others. The crypt of the Alexander Nevsky cathedral holds a collection of Eastern Orthodox icons from the 9th to the 19th century. Other museums are the National Historical Museum with a collection of more than 600,000 items; the National Polytechnical Museum with more than 1,000 technological items on display; the National Archaeological Museum and the Museum of Natural History. The SS. Cyril and Methodius National Library houses the largest national collection of books and documents (1,714,211 books and some 6 million other documents) and is Bulgaria's oldest cultural institute. The Boyana Church, a UNESCO World Heritage site, contains realistic frescoes, depicting more than 240 human images and a total 89 scenes, were painted. With their vital, humanistic realism they are a Renaissance phenomenon at its culmination phase in the context of the common-European art. Muzeiko is a new museum opened in 2015. It is a space with over 130 interactive games created for children and curious adults. The entire content of the museum is designed to inspire children to learn, discover and explore the sciences, while helping children, their families and educators spend time together actively and effectively.
An important facette of cultural life in Sofia are its contemporary art practices and venues.Sofia Arsenal - Museum for Contemporary Art. As contemporary performative arts are beginning to thrive in the last decades, an independent performative art scene has evolved.
Cinema is the most popular form of entertainment. In recent years, cinematic venues have been concentrated in trade centres and malls, and independent halls have been closed. Mall of Sofia holds one of the largest IMAX cinemas in Europe. Most films are American productions, although European and domestic films are increasingly shown. Odeon (not part of the Odeon Cinemas chain) shows exclusively European and independent American films, as well as 20th century classics. Bulgaria's once thriving film industry, concentrated in the Boyana Film studios, has suffered a period of decay after 1990. A relative revival of the industry began after 2001. After the acquisition of Boyana Film by Nu Image, several moderately successful productions have been shot in and around Sofia, such as The Contract, The Black Dahlia, Hitman and Conan the Barbarian and Spartacus. The Nu Boyana Film studios have also hosted some of the scenes for The Expendables 2.
The city houses many cultural institutes such as the Russian Cultural Institute, the Polish Cultural Institute, the Hungarian Institute, the Czech and the Slovak Cultural Institutes, the Italian Cultural Institute, the French Cultural Institute, Goethe Institut, British Council, Instituto Cervantes, and the Open Society Institute, which regularly organise temporary expositions of visual, sound and literary works by artists from their respective countries.
Some of the biggest telecommunications companies, TV and radio stations, newspapers, magazines, and web portals are based in Sofia, including the Bulgarian National Television, bTV and Nova TV. Top-circulation newspapers include 24 Chasa and Trud.
Sofia is one of the most visited tourist destinations in Bulgaria alongside coastal and mountain resorts. Among its highlights is the Alexander Nevsky Cathedral, one of the symbols of Bulgaria, constructed in the late 19th century. It occupies an area of 3,170 square metres (34,122 square feet) and can hold 10,000 people.
The National Historical Museum in Boyana district has a vast collection of more than 650,000 historical items dating from Prehistory to the modern era, although only 10,000 of them are permanently displayed due to the lack of space. Smaller collections of items related mostly to the history of Sofia are in the National Archaeological Museum, a former mosque located between the edifices of the National Bank and the Presidency. Two natural sciences museums — the Natural History Museum and the Earth and Man — display minerals, animal species (alive and taxidermic) and rare materials. The Ethnographic Museum and the National Museum of Military History are other places of interest, holding large collections of Bulgarian folk costumes and armaments, respectively.
Vitosha Boulevard, also called Vitoshka, is a pedestrian zone with numerous cafés, restaurants, fashion boutiques, and luxury goods stores. Sofia's geographic location, in the foothills of the weekend retreat Vitosha mountain, further adds to the city's specific atmosphere.
A large number of sports clubs are based in the city. During the Communist era most sports clubs concentrated on all-round sporting development, therefore CSKA, Levski, Lokomotiv and Slavia are dominant not only in football, but in many other team sports as well. Basketball and volleyball also have strong traditions in Sofia. A notable local basketball team is twice European Champions Cup finalist Lukoil Akademik. The Bulgarian Volleyball Federation is the world's second-oldest, and it was an exhibition tournament organised by the BVF in Sofia that convinced the International Olympic Committee to include volleyball as an olympic sport in 1957. Tennis is increasingly popular in the city. Currently there are some ten tennis court complexes within the city including the one founded by former WTA top-ten athlete Magdalena Maleeva.
Sofia applied to host the Winter Olympic Games in 1992 and in 1994, coming 2nd and 3rd respectively. The city was also an applicant for the 2014 Winter Olympics, but was not selected as candidate. In addition, Sofia hosted Eurobasket 1957 and the 1961 and 1977 Summer Universiades, as well as the 1983 and 1989 winter editions. In 2012, it hosted the FIVB World League finals.
The city is home to a number of large sports venues, including the 43,000-seat Vasil Levski National Stadium which hosts international football matches, as well as the Georgi Asparuhov Stadium and Lokomotiv Stadium, the main venues for outdoor musical concerts. Armeets Arena holds many indoor events and has a capacity of up to 19,000 people depending on its use. The venue was inaugurated on 30 July 2011, and the first event it hosted was a friendly volleyball match between Bulgaria and Serbia. There are two ice skating complexes — the Winter Sports Palace with a capacity of 4,600 and the Slavia Winter Stadium with a capacity of 2,000, both containing two rinks each. A velodrome with 5,000 seats in the city's central park is currently undergoing renovation. There are also various other sports complexes in the city which belong to institutions other than football clubs, such as those of the National Sports Academy, the Bulgarian Academy of Sciences, or those of different universities. There are more than fifteen swimming complexes in the city, most of them outdoor. Nearly all of these were constructed as competition venues and therefore have seating facilities for several hundred people.
There are two golf courses just to the east of Sofia — in Elin Pelin (St Sofia club) and in Ihtiman (Air Sofia club), and a horseriding club (St George club).
Population growth over the years (in thousands):
According to 2016 data, the city has a population of 1,304,772 and the whole Sofia Capital Municipality of 1,441,918. The first census carried out in February 1878 by the Russian Army recorded a population of 11,694 inhabitants including 6,560 Bulgarians, 3,538 Jews, 839 Turks and 737 Romani.
The ratio of women per 1,000 men was 1,102. The birth rate per 1000 people was 12.3 per mille and steadily increasing in the last 5 years, the death rate reaching 12.1 per mille and decreasing. The natural growth rate during 2009 was 0.2 per mille, the first positive growth rate in nearly 20 years. The considerable immigration to the capital from poorer regions of the country, as well as urbanisation, are among the other reasons for the increase in Sofia's population. The infant mortality rate was 5.6 per 1,000, down from 18.9 in 1980. According to the 2011 census, people aged 20–24 years are the most numerous group, numbering 133,170 individuals and accounting for 11% of the total 1,202,761 people. The median age is 38 though. According to the census, 1,056,738 citizens (87.9%) are recorded as ethnic Bulgarians, 17,550 (1.5%) as Romani, 6,149 (0.5%) as Turks, 9,569 (0.8%) belonged to other ethnic groups, 6,993 (0.6%) do not self-identify and 105,762 (8.8%) remained with undeclared affiliation. This statistic should not necessarily be taken at face value due to conflicting data – such as for the predominantly Roma neighbourhood of Fakulteta, which alone may have a population of 45,000.
According to the 2011 census, throughout the whole municipality some 892,511 people (69.1%) are recorded as Eastern Orthodox Christians, 10,256 (0.8%) as Protestant, 6,767 (0.5%) as Muslim, 5,572 (0.4%) as Roman Catholic, 4,010 (0.3%) belonged to other faith and 372,475 (28.8%) declared themselves irreligious or did not mention any faith. The data says that roughly a third of the total population have already earned a university degree. Of the population aged 15–64 – 265,248 people within the municipality (28.5%) are not economically active, the unemployed being another group of 55,553 people (6%), a large share of whom have completed higher education. The largest group are occupied in trading, followed by those in manufacturing industry. Within the municipality, three quarters, or 965,328 people are recorded as having access to television at home and 836,435 (64.8%) as having internet. Out of 464,865 homes – 432,847 have connection to the communal sanitary sewer, while 2,732 do not have any. Of these 864 do not have any water supply and 688 have other than communal. Over 99.6% of males and females aged over 9 are recorded as literate. The largest group of the population aged over 20 are recorded to live within marriage (46.3%), another 43.8% are recorded as single and another 9.9% as having other type of coexistence/partnership, whereas not married in total are a majority and among people aged up to 40 and over 70. The people with juridical status divorced or widowed are either part of the factual singles or those having another type of partnership, each of the two constitutes by around 10% of the population aged over 20. Only over 1% of the juridically married do not de facto live within marriage. The families that consist of two people are 46.8%, another 34.2% of the families are made up by three people, whereas most of the households (36.5%) consist of only one person.
Sofia was declared the national capital in 1879. One year later, in 1880, it was the fifth-largest city in the country after Plovdiv, Varna, Ruse and Shumen. Plovdiv remained the most populous Bulgarian town until 1892 when Sofia took the lead. The city is the hot spot of internal migration, the capital population is increasing and is around 17% of the national, thus a small number of people with local roots remain today, they dominate the surrounding rural suburbs and are called Shopi. Shopi speak one of the transitional South Slavic dialects, along with Torlakian, sharing features with both eastern (Bulgarian and Macedonian) and western (Serbo-Croatian) branches, although they are given non-Slavic origin through the ancient Thracian Serdi, the founders of the city.
Sofia is the economic heart of Bulgaria and home to most major Bulgarian and international companies operating in the country, as well as the Bulgarian National Bank and the Bulgarian Stock Exchange. The city's GDP PPS per capita at current market prices stood at €26,700 ($35,500) in 2013, which was 100% of the then EU average, according to Eurostat data – well above the same year's national average of 47%. The city and its surrounding Yugozapaden NUTS II planning region had a per capita PPS GDP of €20,600 in 2014, higher than any other region in the country. In 2008, the average per capita annual income was 4,572 leva ($3,479). For the same year, the strongest sectors of the city's economy in terms of annual production were manufacturing ($5.5 bln.), metallurgy ($1.84 bln.), electricity, gas and water supply ($1.6 bln.) and food and beverages ($778 mln.). Economic output in 2011 amounted to 15.9 billion leva, or $11.04 billion. The average monthly gross wages paid in December 2015 amount to €645, the highest in Bulgaria and the lowest among EU capitals.
In 2015, Forbes listed Sofia as one of the top 10 places in the world to launch a startup business, because of the low corporate tax (10%), the extremely fast internet connection speed available – one of the fastest in the world, and the presence of several investment funds, including Eleven Startup Accelerator, LAUNCHub and Neveq. In 2015 Globalization and World Cities Research Institute ranked Sofia as Beta- world city.
Historically, after World War II and the era of industrialisation under socialism, the city and its surrounding areas expanded rapidly and became the most heavily industrialised region of the country. The influx of workers from other parts of the country became so intense that a restriction policy was imposed, and residing in the capital was only possible after obtaining Sofianite citizenship. However, after the political changes in 1989, this kind of citizenship was removed.
Increasingly, Sofia is becoming an outsourcing destination for multinational companies, among them IBM, Hewlett-Packard, SAP, Siemens, Software AG. Bulgaria Air, PPD, the national airline of Bulgaria, has its head office on the grounds of Sofia Airport. From 2007 to 2011, the city attracted a cumulative total of $11.6 billion in foreign direct investment.
Up until 2007 Sofia experienced rapid economic growth. In 2008, apartment prices increased dramatically, with a growth rate of 30%. In 2009, prices fell by 26%.
In January 2015 Sofia was ranked 30th out of 300 global cities in terms of combined growth in employment and real gross domestic product (GDP) per capita in 2013–2014. This was the highest rank amongst cities in Southeast Europe. The real GDP (PPP) per capita growth was 2.5% to $33,105 (28,456 euro) and the employment went up by 3.4% to 962,400 in 2013–2014.
With its developing infrastructure and strategic location, Sofia is a major hub for international railway and automobile transport. Three of the ten Pan-European Transport Corridors cross the city: IV, VIII and X. All major types of transport (except water) are represented in the city. The Central Railway Station is the primary hub for domestic and international rail transport. Sofia has 186 km (116 miles) of railway lines. Sofia Airport handled 4,980,387 passengers in 2016.
Public transport is well-developed with bus (2,380 km (1,479 mi)), tram (308 km (191 mi)) and trolleybus (193 km (120 mi)) lines running in all areas of the city. The Sofia Metro became operational in 1998, and now has two lines and 34 stations. As of 2012, the system has 39 km (24 mi) of track. Six new stations were opened in 2009, two more in April 2012, and eleven more in August 2012. In 2015 new 7 stations were opened and the subway extends to Sofia Airport on its Northern branch and to Business Park Sofia on its Southern branch. On July 2016 the Vitosha Metro Station was opened on the M2 main line. A third line is currently under construction and is expected to be finished in the second half of 2019. This line will complete the proposed subway system of three lines with about 65 km (40 mi) of lines. The master plan for the Sofia Metro includes three lines with a total of 63 stations. In recent years the marshrutka, a private passenger van serving fixed routes, proved an efficient and popular means of transport by being faster than public transport, but cheaper than taxis. As of 2005 these vans numbered 368 and serviced 48 lines around the city and suburbs. There are around 13,000 taxi cabs operating in the city. Low fares in comparison with other European countries, make taxis affordable and popular among a big part of the city population.
Private automobile ownership has grown rapidly in the 1990s; more than 1,000,000 cars were registered in Sofia after 2002. The city has the 4th-highest number of automobiles per capita in the European Union at 546.4 vehicles per 1,000 people. The municipality was known for minor and cosmetic repairs and many streets are in a poor condition. This is noticeably changing in the past years. There are different boulevards and streets in the city with a higher amount of traffic than others. These include Tsarigradsko shose, Cherni Vrah, Bulgaria, Slivnitsa and Todor Aleksandrov boulevards, as well as the city's ring road, where long chains of cars are formed at peak hours and traffic jams occur regularly. Consequently, traffic and air pollution problems have become more severe and receive regular criticism in local media. The extension of the underground system is hoped to alleviate the city's immense traffic problems.
Sofia has an extensive district heating system based around four combined heat and power (CHP) plants and boiler stations. Virtually the entire city (900,000 households and 5,900 companies) is centrally heated, using residual heat from electricity generation (3,000 MW) and gas- and oil-fired heating furnaces; total heat capacity is 4,640 MW. The heat distribution piping network is 900 km (559 mi) long and comprises 14,000 substations and 10,000 heated buildings.
Sofia concentrates a significant portion of the national higher education capacity, including 109,000 university and college students and 22 of Bulgaria's 51 higher education establishments. These include four of the five highest-ranking national universities – Sofia University (SU), University of Architecture, Civil Engineering and Geodesy, the Technical University of Sofia, University of National and World Economy and the University of Mining and Geology. Sofia University was founded in 1888. More than 20,000 students study in its 16 faculties. A number of research and cultural departments operate within SU, including its own publishing house, botanical gardens, a space research centre, a quantum electronics department, and a Confucius Institute Rakovski Defence and Staff College, the National Academy of Arts, and Sofia Medical University are other major higher education establishments in the city.
There are 5 primary, 77 middle and 187 secondary schools, of all 77 are private. Education institutions include 13 specialised for children with disabilities, 8 art schools, 22 professional colleges. 35 professional high schools, 25 profiled high schools and 4 sport schools. The "elite" secondary language schools provide education in a selected foreign language. These include the First English Language School, Sofia High School of Mathematics, 91st German Language School, 164th Spanish Language School, and 9th French Language School. Some of them provide a language certificate upon graduation, while the 9th French Language School has exchange programs with a number of lycées in France and Switzerland, such as the Parisian Collège-lycée Jacques-Decour. The American College of Sofia, a private secondary school which developed from a school founded by American missionaries in 1860, is among the oldest American educational institutions outside of the US.
Other institutions of national significance, such as the Bulgarian Academy of Sciences (BAS) and the SS. Cyril and Methodius National Library are located in Sofia. BAS is the centrepiece of scientific research in Bulgaria, employing more than 4,500 scientists in various institutes, including the Bulgarian Space Agency.
Serdica Peak on Livingston Island in the South Shetland Islands, Antarctica is named after Serdica.