 During this period stone circles and henges were built across the county and today 'Cumbria has one of the largest number of preserved field monuments in England'.While not part of the region conquered in the Romans' initial conquest of Britain in AD 43, most of modern-day Cumbria was later conquered in response to a revolt deposing the Roman-aligned ruler of the Brigantes in AD 69.The Romans built a number of fortifications in the area during their occupation, the most famous being UNESCO World Heritage Site Hadrian's Wall which passes through northern Cumbria.