Observations were made during a watching brief at the Abbey Field sports pitches, south of Circular Road North, Colchester, in October 2006. A trench 245m long and 300mm wide was excavated by contractors under archaeological supervision to lay replacement electricity cables in an earlier cable trench. Four archaeological features were observed. Three of these features are associated with the Roman Circus; the in situ remains of the southern outer cavea wall foundation and the robbed-out wall lines of the central barrier or spina. The fourth, F4, was a pit of post-Roman date cut into the subsoil to the south of the outer wall F3. It contained residual Roman building material which is likely to be associated with the robbing out of the structure in the late or immediately post-Roman period. The excavation of the earlier cable trench in 2000 damaged the upper level of the outer wall foundation, and appears to have removed all traces of the inner cavea wall foundation.<1>