Barnfield Pit is the site of a gravel quarry near the village of Swanscombe in the north west of the English county of Kent.

The area was already famous for the finds of numerous Palaeolithic handaxes, mostly Acheulean and Clactonian. In 1935 work at Barnfield Pit produced a few 350,000 year-old fossilised skull fragments that were hailed as the remains of Swanscombe Man.

The remains were in the lower middle terrace gravels at a depth of almost 8m beneath the surface. They were found by Alvan T Marston who visited the pit during the quarrying operations to search for flint tools.

Excavations were carried out by Dr. John d'Arcy Waechter between 1968-72 which revealed the extent of the former shoreline that the bones were found on along with further animal bone and flint tool examples. Most of the finds are now in the Natural History Museum in London.