The granite (or more specifically adamellite) was intruded at depth as a pluton into the surrounding sedimentary rocks during the Carboniferous period, probably about 309 million years ago.

As much of the national park is covered in thick layers of peat (decaying vegetation), the rain is usually absorbed quickly and distributed slowly, so the moor is rarely dry.

[dubious – discuss] At Princetown, near the centre of the moor at a height of 453 metres (1,486 ft), January and February are the coldest months with mean minimum temperatures around 1 °C (34 °F).

Compared with Teignmouth, which is on the coast about 22 miles (35 km) to the east, the average maximum and minimum temperatures are 3.0 °C (5.4 °F) and 2.6 °C (4.7 °F) lower respectively, and frost is at least five times as frequent.

[18] A large variety of bird species can be found on Dartmoor including ones that have declined elsewhere in the UK, such as skylark and common snipe; some are even rare nationally, such as the ring ouzel and the cuckoo.

[21] The upper reaches of the rivers are spawning grounds for Salmon and trout; Palmate newts, frogs and toads breed in the numerous small pools.

[22] The farmland in the wet valleys around the edge of the moors is the most important habitat for insects, including: the marsh fritillary butterfly, southern damselfly, narrow-bordered bee hawkmoth and bog hoverfly.

The old oak woodlands have a distinctive group of insects including the blue ground beetle and Heckford's pygmy moth, a species found nowhere else in the world.

The large systems of Bronze Age fields, divided by reaves, cover an area of over 10,000 hectares (39 sq mi) of the lower moors.

Over the centuries these Neolithic practices greatly expanded the upland moors, and contributed to the acidification of the soil and the accumulation of peat and bogs.

The most significant sites include: There are also an estimated 5,000 hut circles still surviving although many have been raided over the centuries by the builders of the traditional dry stone walls.

The climate became wetter and cooler over the course of a thousand years from around 1000 BC, resulting in much of high Dartmoor being largely abandoned by its early inhabitants.

Like their ancient predecessors, they used the natural granite to build their homes, preferring a style known as the longhouse; some of theses are still inhabited today, although they have been clearly adapted[clarification needed] over the centuries.

In January 2023, in a high court judgement in a case brought by landowner Alexander Darwall, the right for members of the public to wild camp on Dartmoor was lost.

Julian Flaux, the chancellor of the high court, ruled: "In my judgment, on the first issue set out at [14] above, the claimants are entitled to the declaration they seek that, on its true construction, section 10(1) of the 1985 Act does not confer on the public any right to pitch tents or otherwise make camp overnight on Dartmoor Commons.

The Ministry of Defence (MoD) uses three areas of the northern moor for manoeuvres and live-firing exercises, totalling 108.71 km2 (41.97 sq mi),[1] or just over 11% of the National Park.

Red and white posts mark the boundaries of these military areas (shown on Ordnance Survey 1:25,000 scale maps).

controversy has surrounded the work of industrial conglomerates Imerys and Sibelco (formerly Watts Blake Bearne), who have used parts of the moor for china clay mining.

[36] The British government has made promises to protect the integrity of the moor; however, the cost of compensating companies for these licences, which may not have been granted in today's political climate, could prove prohibitive.

The designated Dartmoor National Park area has a resident population of about 33,000,[1] which swells considerably during holiday periods with incoming tourists.

[44] A few stories have emerged in recent decades, such as the "hairy hands", that are said to attack motorists on the B3212 near Two Bridges;[45] and the "Beast of Dartmoor", a supposed big cat.

[46] Dartmoor has inspired a number of artists and writers, such as Sir Arthur Conan Doyle in The Hound of the Baskervilles and The Adventure of Silver Blaze, Bertram Fletcher Robinson,[47][48][49][50] R. D. Blackmore, Eden Phillpotts, Beatrice Chase, Agatha Christie, Rosamunde Pilcher, Gilbert Adair and the Reverend Sabine Baring-Gould.

In 1820, the newly formed Royal Society of Literature offered a prize for a poem on the subject of Dartmoor, this being won by Felicia Hemans.

In Harry Potter and the Goblet of Fire, the fictional 1994 Quidditch World Cup final between Ireland and Bulgaria was hosted on Dartmoor.

[51][52] Dartmoor was the fictional location of a Ministry of Defence animal testing centre called 'Baskerville' in the second series of the multi-award-winning BBC drama Sherlock.

[55] Until the early 19th century Dartmoor was not considered to be a place worth visiting: in the 1540s John Leland wrote in his Itinerary that "Dartmore is muche a wilde Morish and forest Ground", and even by 1789 Richard Gough's opinion was that it is a "dreary mountainous tract".

[56] At the turn of the 19th century John Swete was one of the first people to visit Dartmoor for pleasure and his journals and watercolour paintings now provide a valuable historical resource.

William Crossing's definitive Guide to Dartmoor was published in 1909, and in 1938 a plaque and letterbox in his memory were placed at Duck's Pool on the southern moor.

Other activities are rock climbing on the granite tors and outcrops, some of the well-known venues being Haytor, Hound Tor and The Dewerstone;[61] horse riding, which can be undertaken on any of the common land;[62] cycling (but not on open moorland);[63] and angling for wild brown trout, sea trout and salmon (although much of the river fishing on Dartmoor is privately owned, permits are available for some stretches[64]) .

The park's main visitor centre is located in Princetown and features exhibits about Dartmoor's history, culture and wildlife, as well as changing displays of local art.