Happisburgh Site 3 was discovered in 2005 during a survey of a 2 km stretch of eroding coastal cliff between Happisburgh and Ostend (Parfitt et al. 2010). The cliffs are formed of glacial sediments of MIS 12 age. Beneath the glacial sediments lie a complex series of channels filled with fluvial gravels interdigitating with laminated silts and sands of estuarine origin, laid down by a large river. The lithology of the gravels suggests that the site lay on a course of the proto-Thames. The dating is based on reversed palaeomagetism, biostratigraphy and lithostratigraphy, which in combination indicate an Early Pleistocene age between c. 0. 78 and 1.0 Ma (Parfitt et al. 2010). The sediments contain a rich array of environmental data, including pollen, plant macros, foraminifera, ostracods, beetles, molluscs and vertebrate remains. The pollen sequence indicates a cooling climate with a regional vegetation change from deciduous woodland to conifer dominated forest. There are two cooling phases in the late Early Pleistocene to which the site might date of either 950,000 or 850,000 years ago. In combination the fauna and flora indicate that the local environment was a mix of grassland and marshy pools on the edge of the river with occasional indications of saltmarsh and brackish water. The archaeology consists of over 170 flint artefacts, the majority from the gravel of bed E, but also from beds D and C. They are in a very fresh condition and can be regarded as being in primary context.