A field walking evaluation was conducted over a 62 hectare area of land which coincides with the arable areas of the Colchester Garrison PFI site, Colchester. Only three classes of archaeological material were found in any quantity: burnt flint (prehistoric), Roman tile, and post-medieval pottery. General spreads of burnt flints and Roman tile indicate areas of activity in the prehistoric and Roman periods. Within those general spreads were significant clusters of Roman tile (three clusters), as defined by the Essex field walking methodology. It is not clear whether the concentrations of Roman tile indicate the position(s) of Roman buildings or whether they are simply manure scatter finds, but they probably represent the latter. The post-medieval pottery is probably on the site as a result of manuring operations which used material from local farms. The geophysical survey ran concurrently with the field walking. There were some instances where ‘anomalies’ detected by the geophysical survey were quite clearly archaeological features already known as cropmarks. This was particularly so of a number of double-ditched trackways. Where there was a direct correlation, the cropmark plots were corrected to the anomaly positions. In other cases, geophysical anomalies probably represent previously unknown archaeological features, perhaps field boundaries, which add further detail to the picture of the late prehistoric and Roman landscape now being built up by these various archaeological survey techniques. <1>