A watching brief was carried out by Colchester Archaeological Trust during the construction of a new pavilion at the Colchester Garrison Athletics Facility on Abbey Field.<1> Eight archaeological features were recorded. Of these, three ditches and one pit are tentatively dated to the Roman period. Two of the ditches were orientated N to S, and formed part of a ditched trackway. These correspond with two ditches (F58 & F120), dated as Roman, located on the Garrison sports pitch just to the north of the present site (CAT Report 138).<2> The third ditch was a boundary ditch orientated E to W that appeared to abut the eastern edge of the trackway. The pottery from Ditch F1 included sherds from the lower half of a Roman jar of probable mid 1st-2nd century date, possibly from a disturbed burial. Continuous archaeological supervision was undertaken during the following groundworks: • The pit for a percolation test, c.1.8m deep. • The foundation trenches for the relocated floodlights, c.1.8m deep. • The footings for the new pavilion, c.1.1m deep. • The pit for a new pump station, c.2m deep. • The trench for the new services, c.0.6m deep. • The pit for a new soakaway, c.2m deep. The development site was covered by a layer of turf and a homogenous dark brown sandy-silt topsoil (L1). L1 was generally around 300mm deep and contained modern and post-medieval finds. Beneath L1 was a layer of buried topsoil (L2, c.350mm thick) which was discernibly lighter in colour than L1 and did not contain modern finds. L2 sealed natural ground (L3), a medium orange sand with isolated patches of gravel. The archaeological features were cut from within the buried topsoil (L2) and were only distinguishable once natural L3 had been reached. Roman, medieval and post-medieval pottery sherds, animal bone, clay pipe, nails, glass, and a traders token were all collected from L2. Numerous modern services, mostly electricity cables, were also encountered within L2.