The island was first inhabited by people who crossed over the land bridge from the European mainland. Traces of early humans have been found (at Boxgrove Quarry, Sussex) from some 500,000 years ago and modern humans from about 30,000 years ago. Until about 10,000 years ago, Great Britain was joined to Ireland, and as recently as 8,000 years ago it was joined to the continent by a strip of low marsh to what is now Denmark and the Netherlands. In Cheddar Gorge, near Bristol, the remains of animal species native to mainland Europe such as antelopes, brown bears, and wild horses have been found alongside a human skeleton, 'Cheddar Man', dated to about 7150 BC. Thus, animals and humans must have moved between mainland Europe and Great Britain via a crossing.