A defensive system built to protect Camulodunum dating from around 100BC. Camulodunum was not a town in the modern sense, but was more like a large country estate. It covered some 12 square miles and included commercial, industrial and farming settlements as well as the Royal household of the Trinovantes tribe. These settlements were enclosed and protected by an elaborate system of earthwork embankments, known as dykes, much of which survives today. These can mostly be seen along Straight Road.