In 55 B.C. Julius Caesar came, saw, conquered and then left. It was not until A.D. 43 that the Emperor Claudius crossed the channel and made Britain the western outpost of the Roman Empire that would span from the Scottish border to Persia. For the next 400 years the island would be transformed. Within that period would see the rise of Londinium, almost immediately burnt to the ground in A.D. 60 by Boudicca; Hadrian's Wall, which was constructed in A.D. 112 to keep the northern tribes at bay, as well as the birth of the Emperor Constantine in third century York.