Hengiform monument

A Hengiform monument (also known as a Dorchester henge) is a name given by archaeologists to prehistoric monuments which resemble henges but have a diameter of less than 20m. They are distributed throughout England and into southern Scotland though no examples have been found in Wales.

They consist of a flat, roughly circular area of ground, typically between 5m and 20m in diameter, enclosed within a low earthwork consisting of a ditch inside a bank. As with henges there may be either one entrance through the earthwork, or two opposing entrances. Pits, cremations, postholes, stone-sockets and graves have been found within them, and postholes and cremation pits have also been found to be present close to the site in some cases.

In plan, a hengiform monument can be mistaken for a ploughed-out round barrow, although the former tend to be slightly larger and their earthworks more substantial. As with henges, they are thought to have served ritual purposes connected with burial and are thought to be of late Neolithic date.

Only around 50 are known with examples at Barforddn and Dorchester-on-Thames.