It is indeed and it was called Camulodunum. It is STILL a garrison town. It has a castle, mostly Norman, I believe, built on the foundations of the original Roman temple. The castle is now a museun WELL worth looking at. The town is set on a hill, as you would expect of a fortification, and is still surrounded by the remains of the old Roman wall. I used to live on the Roman road which ran from London to Colchester.