Summary. This is a summary report on an archaeological watching brief undertaken during site investigations at Taylor Wimpey's Garrison Alienated Land (GAL) redevelopment Area B1b (Flagstaff Compound), Colchester Garrison, Colchester, Essex. The ground investigations were undertaken by Merebrook Consulting Ltd in September 2013 in advance of the proposed redevelopment of the site. All groundworks were subject to archaeological monitoring due to the sites location within the southern and western part of the walled precinct of St John's Abbey (SAM no 26307) and the presence of the eastern end of the Roman circus.