Monument record MNL 639 - RAF Mildenhall, Washington Square, Mildenhall.

2010: Archaeological excavations have taken place over an area of approximately 3,700 square metres on Washington Square RAF Mildenhall. The work followed on from a trenched evaluation that took place after the surface of the car park that occupied the site had been removed.

The site lies approximately 5m above sea level and was very close to the edge of the fens from prehistoric times up until the post medieval periods when large areas were drained. The fens included many square miles of inland marsh and wetland surrounded by an area of light sandy soil. These conditions were favourable for grazing cattle and sheep and ploughing, which could be done with light tools, and hunting in the wetland itself.

The evidence at Washington Square adds to work already carried out at Heritage Park (MNL 532), which is probably part of the same settlement. Post excavation work has not started and any conclusions are tentative, but subject to confirmation the early evidence shows a multi period site with field systems and enclosures dating from the Late Iron Age to the post-medieval period.

The earliest clear settlement evidence is for numerous re-cut ditches running northeast-southwest across the south east end of the site which are Late Iron Age to early Roman. They seem to suggest a sequence of enclosures that was centred to the east of the site. There are a number of pits that are provisionally interpreted as waterholes that are concentrated in the lower areas and theses are also thought to be late Iron Age/Early Roman.

There are at least three more separate phases dating to the Roman period. The alignment of the enclosures changes and they extend west across the site. The second of these enclosures is related to a Roman field system that can be traced over large areas. It consists of a series of parallel ditches that must have been related to planting, although what was being grown is unknown at present. The latest enclosure ditches were infilled with Roman finds including animal bone and large amounts of pottery; it is clear from this that people were living on or next to the site and disposing of rubbish in the adjacent ditches. The pottery has not yet been washed and examined but early signs show a significant amount from the late 3rd to 4th centuries. The site was metal detected at various times and this has led to the recovery of an Iron Age brooch and two enamelled Roman disc brooches, one of which was gilded. A large enamelled horse fitting was also found. Coins from the site include a group of 5 that are silver and date from the Iron Age.

To date four crouched burials, with a fourth laid out on a north-south axis in a ditch with the head at the north end, have been found. At least one is Roman but the others are not dated at present.

2012: In addition to the above, Post excavation assessment confirmed that the earliest ditches which have been re-cut many times, are late Iron Age to early Roman. They seem to suggest a sequence of enclosures. There are three more phases of dating to the Roman period. The alighnment of the enclosures changes towards west of the site. The latest enclosure ditches were infilled with Roman finds including animal bone and large amounts of pottery. The pottery assemblage confirmed a long period of occupation but with significant quantities dating from the late 3rd to 4th centuries. As well as the finds described above, 18 copper alloy Roman coins and 1 silver Roman coin were also recovered. The crouched burials were radiocarbon dated - three samples failed. The fourth burial is confirmed as Roman. Other features include a network of probable drainage channels dating from the post-medieval period indicating the reclamation of marginal land. Evidence of the WWII base was uncovered with the flagpole stand from the parade ground and three air raid shelters serving the buildings that surrounded the square. (S2).