Butser Ancient Farm, near Petersfield in Hampshire, England, is a working replica of an Iron Age farmstead where long-term experiments in prehistoric and Roman agriculture, animal husbandry and manufacturing are held to test ideas posited by archaeologists. The period of interest is that from 400 BC to 400 AD.
Butser Ancient Farm was founded in 1972 by experimental archaeologist Peter J Reynolds (6 November 1939 – 26 September 2001), and named after its original site at Butser Hill, a few kilometres from Petersfield. In 1976 a second site was opened at Hillscombe Down about a kilometre away, and in 1989 the original site at Butser Hill was closed down. In 1991 the project moved to Bascomb Copse on the slopes of Windmill Hill, Hampshire between Chalton, Hampshire and Clanfield, Hampshire, about 5 km from the original site.
Buildings at the farm include simulated pre-Roman roundhouses and a simulated Roman villa. The Pimperne House was the first full-sized roundhouse to be built at the site, and at the time the largest in western Europe.
The Doctor Who serial The Mysterious Planet was filmed at the farm. An episode of the 2005 BBC Television documentary series What the Ancients Did for Us examining the ideas and inventions of the Ancient Britons was filmed here.
The farm is open to the public.