The Coromandel Peninsula was named for HMS Coromandel (originally named HMS Malabar), a ship of the British Royal Navy, which stopped at Coromandel Harbour in 1820 to purchase kauri spars and was itself named for India's Coromandel Coast.
The peninsula is steep and hilly, and is largely covered in temperate rainforest. The Coromandel Range forms a spine for the peninsula, rising to nearly 900 metres, and the large island of Great Barrier, which lies beyond the northern tip, can be thought of as an extension of the range. Great Barrier is separated from Cape Colville on the peninsula's northern coast by the Colville Channel.
Although the peninsula is close to large centres of population such as Auckland to the west and Tauranga to the southeast, its rugged nature means that much of it is relatively isolated, and the interior and northern tip are both largely undeveloped and sparsely inhabited. A forest park covers much of the peninsula's interior.
Numerous small islands and island groups lie offshore, such as the Motukawao Islands to the northwest, the Alderman Islands and Slipper Island to the southeast, and the Mercury Islands to the northeast.
The peninsula shows considerable signs of past volcanism. It comprises the eroded remnants of the Coromandel Volcanic Zone, which was highly active during the Miocene and Pliocene periods. Volcanic activity has since primarily shifted southeast to the Taupo Volcanic Zone, although Mayor Island was recently active some 25 km to the east. Geothermal activity is still present on the Peninsula, with hot springs in several places, notably at Hot Water Beach, in the central east coast between Whitianga and Tairua.
Owing to the nature of the land, much of the Coromandel's population clusters in a small number of towns and communities along the southeastern and southwestern coasts.
Only five towns on the peninsula have populations of over 1000 (Coromandel, Whitianga, Thames, Tairua, and Whangamata), and of these only Thames has a population of over 5000. Several small towns dot the coast of the Firth of Thames in the southwest. Other small towns on the peninsula include Te Puru, Matarangi, Whangapoua, Whiritoa, Hikuai, Port Jackson, Port Charles, Tairua, Pauanui and Colville. The population of several of these centres is highly seasonal, with many Aucklanders having holiday homes in the Coromandel. During the Christmas and New Year (summer) holiday period, visiting families and travellers from around the North Island significantly increase activity in the area, particularly in Whangamata, Whitianga, Matarangi, Tairua and Pauanui.
The peninsula has become a popular place to live for those who have chosen an alternative lifestyle, especially for those who have elected not to live in Auckland. The 1970s saw thousands of hippies relocate from large cities around New Zealand to the Coromandel in search of an environmentally friendly lifestyle associated with the counterculture back-to-the-land movement. As of 2010, increasing numbers of affluent Aucklanders have started moving to the Coromandel.
The population density decreases with both distance from the coast and distance north. Of the main population centres, only Coromandel, Colville, Matarangi and Whitianga lie in the north of the peninsula, and much of the interior remains virtually uninhabited.
The area was formerly known largely for its hardrock gold mining and kauri industries, but is now a mecca for tourism, especially ecotourism. A forest park occupies much of the centre of the peninsula, and the coasts are dotted with fine beaches and stunning views. The Moehau Ranges even have an imagined monster, the Hairy Moehau.
Evidence of the region's geothermal origins can be found in hot springs, notably at Hot Water Beach on the peninsula's east coast. The town of Whangamata is a popular holiday retreat, and Whitianga on Mercury Bay is renowned for its yachting. The peninsula's waters are also a popular destination for scuba divers.
Cathedral Cove, named for its cathedral like arch through the limestone cliff, is a popular destination, only accessible by boat or on foot.
In recent years, dolphins and more coast-loving whales are appearing along the coasts as their numbers began to recover, such as southern right whale, Bryde's whale and humpback whale.
There are many historical mines in the Coromandel area, especially for gold mining. Waihi, in the south of the peninsula, still has an active gold mine, as of the late 2000s, though most other mining in the area ceased about the 1980s. In late 2009, New Zealand's Energy and Resources Minister Gerry Brownlee (National Party) noted that there was a possibility of new mining in conservation areas, even though he had previously declared that a stocktake of mineral resources in protected areas did not indicate a desire to mine there.
The towns are connected by State Highways 25 and 25A which form a circuit around the peninsula. At the base of the peninsula, the towns of Paeroa and Waihi are connected by means of a road through the Karangahake Gorge which separates the Coromandel Range from the Kaimai Range. Not all of the roads within the peninsula are sealed (i.e. are gravel roads) notably the 309 Road which connects Coromandel Town and Whitianga. Some hire car companies have contracts that specifically exclude driving on these roads. There is also a passenger ferry that runs from Ferry Landing to Whitianga. For pedestrians and cyclists based in Cook's Beach, Flaxmill Bay, Front Beach, and Ferry Landing, this ferry provides direct access to the shops and restaurants of Whitianga. While the ferry takes approximately 5 minutes to cross the harbor, the road around can take 40 to 45 minutes.