The islands are located in the Heligoland Bight in the southeastern corner of the North Sea. They are the only German islands not in the immediate vicinity of the mainland. They lie approximately 69 kilometres by sea from Cuxhaven at the mouth of the River Elbe. During the period of British possession, the lyrics to "Deutschlandlied", which became the national anthem of Germany, were written on one of the islands by August Heinrich Hoffmann in 1841, while he was vacationing there.
In addition to German, the local population, who are ethnic Frisians, speak the Heligolandic dialect of the North Frisian language called Halunder. Heligoland used to be called Heyligeland, or "holy land", possibly due to the island's long association with the god Forseti.
Heligoland is located 46 kilometres (29 mi) off the German coastline and consists of two islands: the populated triangular 1 km2 (0.4 sq mi) main island (Hauptinsel) to the west, and the Düne ("dune", Heligolandic: de Halem) to the east. "Heligoland" generally refers to the former island. Düne is somewhat smaller at 0.7 km2 (0.27 sq mi), lower, and surrounded by sand beaches. It is not permanently inhabited, but is today the location of Heligoland's airport.
The main island is commonly divided into the Unterland ("Lower Land", Heligolandic: deät Deelerlun) at sea level (to the right on the photograph, where the harbour is located), the Oberland ("Upper Land", Heligolandic: deät Boperlun) consisting of the plateau visible in the photographs and the Mittelland ("Middle Land") between them on one side of the island. The Mittelland came into being in 1947 as a result of explosions detonated by the British Royal Navy (the so-called "Big Bang"; see below).
The main island also features small beaches in the north and the south and drops to the sea 50 metres (160 ft) high in the north, west and southwest. In the latter, the ground continues to drop underwater to a depth of 56 metres (184 ft) below sea level. Heligoland's most famous landmark is the Lange Anna ("Long Anna" or "Tall Anna"), a free standing rock column (or stack), 47 metres (154 ft) high, found northwest of the island proper.
The two islands were connected until 1720, when the natural connection was destroyed by a storm flood. The highest point is on the main island, reaching 61 metres (200 ft) above sea level.
Although culturally closer to North Frisia in the German district of Nordfriesland, the two islands are part of the district of Pinneberg in the state of Schleswig-Holstein. The main island has a good harbour and is frequented mostly by sailing yachts.
The German Bight and the area around the island is known to have been inhabited since prehistoric times. Flint tools have been recovered from the bottom of the sea surrounding Heligoland. On the Oberland, prehistoric burial mounds were visible until the late 19th century and excavations showed skeletons and artefacts. Moreover, prehistoric copper plates have been found under water near the island; those plates were almost certainly made on the Oberland.
In 697, Radbod, the last Frisian king, retreated to the then-single island after his defeat by the Franks—so it is written in the Life of Willebrord by Alcuin. By 1231, the island was listed as the property of the Danish king Valdemar II. Archaeological findings from the 12th to 14th century suggest the processing of copper ore on the island.
There is a general understanding that the name Heligoland in origin means "Holy Land" (cf. modern Dutch and German heilig, "holy"). In the course of the centuries several alternative theories have been proposed, explaining the name from a Danish king Heligo or from the Frisian word hallig, meaning "salt marsh island". In this sense, the 1911 Encyclopædia Britannica suggests an etymology of "Hallaglun, or Halligland, i.e. 'land of banks, which cover and uncover'".
Traditional economic activities included fishing, hunting birds and seals, wrecking and—very important for many overseas powers—piloting overseas ships into the harbours of Hanseatic League cities such as Bremen and Hamburg. Moreover, in some periods Heligoland was an excellent base point for huge herring catches. As a result, until 1714 ownership switched several times between Denmark and the Duchy of Schleswig, with one period of control by Hamburg. In August 1714, it was captured by Denmark, and it remained Danish until 1807.
On 11 September 1807, during the Napoleonic Wars, HMS Carrier brought to the Admiralty the despatches from Admiral Thomas Macnamara Russell announcing Heligoland's capitulation to the British. Heligoland became a centre of smuggling and espionage against Napoleon. Denmark then ceded Heligoland to George III of the United Kingdom by the Treaty of Kiel (14 January 1814). Thousands of Germans came to Britain and joined the King's German Legion via Heligoland.
The British annexation of Heligoland was ratified by the Treaty of Paris signed on 30 May 1814, as part of a number of territorial reallocations following on the abdication of Napoleon as Emperor of the French.
The prime reason at the time for Britain's retention of a small and seemingly worthless acquisition was to restrict any future French naval aggression against the Scandinavian or German states. In the event no effort was made during the period of British administration to make use of the islands for naval purposes, partly for financial reasons but principally because the Royal Navy considered Heligoland to be too exposed as a forward base.
In 1826, Heligoland became a seaside spa and soon it turned into a popular tourist resort for the European upper-class. The island attracted artists and writers, especially from Germany and Austria who apparently enjoyed the comparatively liberal atmosphere, including Heinrich Heine and August Heinrich Hoffmann von Fallersleben. More vitally it was a refuge for revolutionaries of the 1830s and the 1848 German revolution.
As related in the Leisure Hour, it was "a land where there are no bankers, no lawyers, and no crime; where all gratuities are strictly forbidden, the landladies are all honest and the boatmen take no tips", while the English Illustrated Magazine provided a description the most glowing terms: "No one should go there who cannot be content with the charms of brilliant light, of ever-changing atmospheric effects, of a land free from the countless discomforts of a large and busy population, and of an air that tastes like draughts of life itself."
Britain gave up the islands to Germany in 1890 in the Heligoland–Zanzibar Treaty. The newly unified Germany was concerned about a foreign power controlling land from which it could command the western entrance to the militarily-important Kiel Canal, then under construction, and other naval installations in the area, and traded for it. A "grandfathering"/optant approach prevented the Heligolanders (as they were named in the British measures) from forfeiting advantages because of this imposed change of status.
Heligoland has an important place in the history of the study of ornithology, and especially the understanding of migration. The book Heligoland, an Ornithological Observatory by Heinrich Gätke, published in German in 1890 and in English in 1895, described an astonishing array of migrant birds on the island and was a major influence on the future studies of bird migration, in Britain in particular.
Under the German Empire, the islands became a major naval base, and during the First World War the civilian population was evacuated to the mainland. The first naval engagement of the war, the Battle of Heligoland Bight, was fought nearby in the first month of the war. The islanders returned in 1918, but during the Nazi era the naval base was reactivated. Lager Helgoland, the Nazi labour camp on Alderney, was named after the island.
Werner Heisenberg (1901–1975) first formulated the equation underlying his picture of quantum mechanics while on Heligoland in the 1920s. While a student of Arnold Sommerfeld at Munich in the early 1920s, Heisenberg first met the Danish physicist Niels Bohr. He and Bohr went for long hikes in the mountains and discussed the failure of existing theories to account for the new experimental results on the quantum structure of matter. Following these discussions, Heisenberg plunged into several months of intensive theoretical research, but met with continual frustration. Finally, suffering from a severe attack of hay fever, he retreated to the treeless (and pollenless) island of Heligoland in the summer of 1925. There he conceived the basis of the quantum theory.
In 1937, construction began on a major reclamation project (Project Hummerschere) intended to expand existing naval facilities and restore the island to its pre-1629 dimensions. The project was largely abandoned after the start of World War II and was never completed.
The area was the setting of the aerial Battle of the Heligoland Bight in 1939, a result of British bombing attempts on German Navy vessels in that area. The area's waters were frequently mined by British aircraft.
Heligoland also had military function as a sea fortress in Second World War. Completed and ready for use were the submarine bunker North sea III, the coastal artillery, an air-raid shelter system with extensive bunker tunnels and the airfield with the air force – Jagdstaffel Helgoland (April to October 1943). Forced labour of, among others, citizens of the Soviet Union was used during the construction of military installations during World War II.
On 3 December 1939, Heligoland was bombed by the Allies for the first time. The attack, by twenty four Wellington bombers of RAF Squadrons 38, 115 and 149, failed to destroy its target of German warships at anchor.
Within three days in early 1940, the Royal Navy lost three submarines in Heligoland: HMS Undine (N48) on 6 January, HMS Seahorse (98S) on 7 January and HMS Starfish on 9 January.
Early in the war, the island was little affected by bombing. This shows the minor military significance of the island for British forces. Through the development of the Luftwaffe, the island had largely lost its strategic importance. The Jagdstaffel Helgoland, temporarily used for defense against Allied bombing, was equipped with a rare version of the Messerschmitt Bf 109 fighter originally designed for use on aircraft carriers.
Shortly before the war ended in 1945, Georg Braun and Erich Friedrichs succeeded in forming a resistance group. However, shortly before they were to execute the plans, they were betrayed by two members of the group. About twenty men were arrested on 18 April 1945; fourteen of them were transported to Cuxhaven. After a short trial, five resisters were executed by firing squad at Cuxhaven-Sahlenburg on 21 April 1945.
To honour them, in April 2010 the Helgoland Museum installed six stumbling blocks on the roads of Heligoland. Their names are Erich P. J. Friedrichs, Georg E. Braun, Karl Fnouka, Kurt A. Pester, Martin O. Wachtel, and Heinrich Prüß.
With two waves of attacks on 18 and 19 April 1945, 1,000 aircraft of the British Royal Air Force dropped about 7,000 bombs. The majority of the population survived in the bomb shelters. 285 people were killed, including many Luftwaffenhelfer and naval auxiliaries. 128 of the casualties were anti-aircraft crew. The bomb attacks rendered the island uninhabitable, and it was evacuated.
From 1945 to 1952 the uninhabited Heligoland islands were used as a bombing range. On 18 April 1947, the Royal Navy detonated 6,700 tonnes of explosives ("Big Bang" or "British Bang"), creating one of the biggest single non-nuclear detonations in history. Though the attack was aimed at the fortifications, the island's total destruction would have been accepted. The blow shook the main island several miles down to its base, changing its shape (the Mittelland was created).
On 20 December 1950, two students and a professor from Heidelberg – René Leudesdorff, Georg von Hatzfeld and Hubertus zu Löwenstein – occupied the off-limits island and raised various German, European and local flags. The students were arrested by the British military and brought back to the mainland. The event started a movement to restore the islands to Germany, which gained the support of the German parliament. On 1 March 1952, Heligoland was returned to German control, and the former inhabitants were allowed to return. The first of March is an official holiday on the island. The German authorities had to clear a huge amount of undetonated ammunition, landscape the main island, and rebuild the houses before it could be resettled.
Heligoland is now a holiday resort and enjoys a tax-exempt status, as it is part of the EU but excluded from the EU VAT area and customs union. Consequently, much of the economy is founded on sales of cigarettes, alcoholic beverages and perfume to tourists who visit the islands. The ornithological heritage of Heligoland has also been re-established, with the Heligoland Bird Observatory, now managed by the Ornithologische Arbeitsgemeinschaft Helgoland e.V. ("Ornithological Society of Heligoland") which was founded in 1991. A search and rescue (SAR) base of the DGzRS, the Deutsche Gesellschaft zur Rettung Schiffbrüchiger ("German Maritime Search and Rescue Service"), is located on Heligoland.
Before the island was connected to the mainland network by a submarine cable in 2009, electricity on Heligoland was generated by a local diesel plant.
Heligoland was the site of a trial of GROWIAN, a large wind turbine testing project. In 1990, a 1.2 MW turbine of the MAN type WKA 60 was installed. Besides technical problems, the turbine was not lightning proof and insurance companies would not provide coverage. The wind energy project was viewed as a failure by the islanders and was stopped. The submarine cable in use now has a length of 53 kilometres (33 mi) and is one of the longest AC submarine power cables in the world and the longest of its kind in Germany. It was manufactured by the North German Seacable Works in a single piece and was laid by the barge Nostag 10 in spring 2009. The Heligoland Power Cable, which is designed for an operational voltage of 30 kV, reaches the German mainland at Sankt Peter-Ording.
Plans to re-enlarge the land bridge between different parts of the island by means of land reclamation came up between 2008 and 2010. However, the local community voted against the project.
Since 2013, a new industrial site is being expanded on the southern harbour. E.ON, RWE and WindMW plan to manage operation and services of large offshore windparks from Heligoland. The range had been cleaned of left-over ammunition.
The climate of Heligoland is typical of an offshore climate, being almost free of pollen and thus ideal for people with pollen allergies. Since there is no land mass in the vicinity, temperatures rarely drop below −5 °C (23 °F) even in the winter. At times, winter temperatures can be higher than in Hamburg by up to 10 °C (18 °F) because cold winds from Russia are weakened. While spring tends to be comparatively cool, autumn on Heligoland is often longer and warmer than on the mainland, and statistically, the climate is generally sunnier. The coldest temperature ever recorded on Heligoland was −11.2 °C (12 °F) in February 1956, while the highest was 28.7 °C (84 °F) in July 1994.
Owing to the mild climate, figs have reportedly been grown on the island as early as 1911, and a 2005 article mentioned Japanese bananas, figs, agaves, palm trees and other exotic plants that had been planted on Heligoland and were thriving. There still is an old mulberry tree in the Upper Town.
The island of Heligoland is a geological oddity; the presence of the main island's characteristic red sedimentary rock in the middle of the German Bight is unusual. It is the only such formation of cliffs along the continental coast of the North Sea. The formation itself, called the Bunter sandstone or Buntsandstein, is from the early Triassic geologic age. It is older than the white chalk that underlies the island Düne, the same rock that forms the white cliffs of Dover in England and cliffs of Danish and German islands in the Baltic Sea. In fact, a small chalk rock close to Heligoland, called witt Kliff (white cliff), is known to have existed within sight of the island to the west until the early 18th century, when storm floods finally eroded it to below sea level.
Heligoland's rock is significantly harder than the postglacial sediments and sands forming the islands and coastlines to the east of the island. This is why the core of the island, which a thousand years ago was still surrounded by a large, low-lying marshland and sand dunes separated from coast in the east only by narrow channels, has remained to this day, although the onset of the North Sea has long eroded away all of its surroundings. A small piece of Heligoland's sand dunes remains—the sand isle just across the harbour called Düne (Dune). A referendum in June 2011 dismissed a proposal to reconnect the main island to the Düne islet with a landfill.
The Heligoland flag is very similar to its coat of arms—it is a tricolour flag with three horizontal bars, from top to bottom: green, red and white
There is an alternative version in which the word Sand ("sand") is replaced with Strand ("beach").
There are very few cars on Heligoland. A special section (§50) in the German traffic regulations (Straßenverkehrsordnung, abbr. StVO) prohibits the use of automobiles and bicycles on the island. No other region in Germany has any exceptions to the general regulations in the StVO, although other North Sea islands, such as Baltrum, have also banned the public from using cars and motorbikes.
Except for the local ambulance van and the small firetrucks, the only motor vehicles on the island are electrically powered and used primarily for moving material. Kick scooters are sometimes used as substitutes for bicycles.
The island received its first police car on 17 January 2006. Until then the island's policemen moved on foot and by bicycle, being exempt from the bicycle ban.