It consists of river gravels, estuary and floodplain sediments predominantly silt, sand, and muds as well as peat along the coast of northern Norfolk.

[1] It is the type locality for the Cromerian Stage of the Pleistocene between 0.8 and 0.5 million years ago.

It is about 6-to-8-metre (20 to 26 ft) thick and is exposed in cliff section near the village of West Runton.

For over a century this formation, named after the local town of Cromer, has been famous for its assemblage of fossil mammal remains, containing the diverse remains of numerous taxa, including deer,[3] carnivorans[4] and birds.

[5] Although most of the forest bed is now obscured by coastal defence, the Cromer Forest-bed Formation continues to be eroded and is rich in fossils including the skeletal remains of the West Runton Mammoth which was discovered in 1990.