A remaining bit of Roman wall at Venta Icenorum, the Roman capital of East Anglia. Originally it would have looked similar to this <a href="https://www.geograph.org.uk/photo/1951409">TG4704 : Burgh Castle Walls</a>. With tiles and knapped flint it would have looked very intimidating. This is along with impressive embankments, on the west side the added defence of the river Tas and the southern eastern parts have more earlier ditches.
The defences where built to defend the most important part of the town, enclosing 35 acres. Other parts like the amphitheatre were outside along with houses and farms. Construction finished by the AD 200s, 4 metre thick walls 7 metres high with 4 entrances and many bastions.
The town was successful until about AD 340 when Roman rule was failing, an uprising in 409 beat off the Romans and by 410 the Roman Army left. The Saxons, Angles and Jutes began to settle here, now Britain became Anglo-Saxon.