Although the so-called vexillation fortress at Osmanthorpe (SK 678563) in the Greet Valley, Nottinghamshire, is a recent discovery, fieldwork in the immediate vicinity of the site has been conducted independent of it in the past. This paper reports the results of recent work connected with what we shall term the castra and brings to wider attention some of the earlier work in the Greet Valley, combined with a consideration of its possible implications.