There is some confusion in the name as George Babington, writing in 1883, calls the town Camboritum, and it is shown by that name on the Ordnance Survey Maps. The better usage is Duroliponte. Camboritum is at Lackford. There is inconclusive evidence of Claudian era ditches at the rear of the Cambridgeshire Archives building.
http://www.pastscape.org.uk/hob.aspx?hob_id=371356 ;
http://www.british-history.ac.uk/rchme/cambs/lix-lxxii ;
http://roman-britain.co.uk/places/duroliponte.htm ;
http://ebooks.cambridge.org/chapter.jsf?bid=CBO9781107589872&cid=CBO9781107589872A007