The Bedfordshire Historic Environment Record [HER] contains information on the county's historic buildings and landscapes and summaries of each entry can now be found online as part of the Heritage Gateway website.
During the Late Iron Age and early Roman period the focus of the Iron Age settlement to the west of Elstow Brook began to move north west. The Late Iron Age enclosure system was largely abandoned and replaced by a rectilinear ‘ladder’ enclosure system associated with a ditched routeway with a large D-shaped enclosure, possibly for stock control, on higher ground at its south eastern end [HER15321]. It seems that flooding had become a problem, but a number of ditched field systems were created to the south-east of the enclosure and another ditched routeway aligned northwest to southeast was created to the west of the enclosure. There is also evidence of cremation burials and an inhumation. During Romano-British times the D-shaped enclosure was superseded by a new enclosure system further north-west and another large D-shaped settlement enclosure, including a cistern which produced the remains of leather shoes and a number of waterlogged structural timbers. The enclosure remained in use into the 3rd and 4th centuries.
A small Late Iron Age / Romano-British cremation cemetery was located in a second area about 30 metres south of Elstow Brook. This contained four urned cremation burials, including an unusual double burial with two urns in the same grave, and two inhumation burials. Around 90 metres to the north-east were a series of ditches and a large, square-shaped pit or cistern which contained pottery dating from the Late Iron Age to the 4th century. Earlier archaeological investigations at the entrance to the Marston Vale Millennium Country Park had previously shown evidence of early settlement in this area, but the site appears to have been little used in Roman times [HER17715].
In 2000 work carried out to the east of Woburn Road in the area of what is now Howes Drive and Drapers End showed prolonged occupation from the Middle Iron Age to the Roman period.
There is speculation that Roman roads may have run through the parish. The line of a supposed road from Dorchester-on-Thames to Alconbury House has been traced through parts of Bedfordshire, but the route between Ridgmont and Wootton has disappeared [HER485]. Similarly, there may have been a road from Ruxox in Flitwick to Irchester, but there is no definite evidence to suggest that it passed through Marston [HER5020]. A possible indicator for a Roman road in the general direction south-east of the church is the survival of the stone known as the Devil’s Toenail which has traditionally been explained by the legend of the Devil’s Jumps. This stone is a limestone pillar with eight sides and a moulded base, standing about half a metre high, with no obvious inscription. It is possible that this was once a Roman milestone.
A substantial number of Roman coins and a brooch were found by a metal detector to the north-east of Marston Thrift [HER15905], and a number of other smaller finds of Roman coins and pottery have been made in the parish.