The Emperor Hadrian built this wall to keep the tribes of the Picts and Scots from invading Roman Britain. It would not keep individuals out, but it would keep an army from invading -- with its necessary wagons for supplies and horses.

It also illustrates the end of Roman expansion. By building this wall (from sea to sea), the Romans admitted that they could neither deal with the tribes in Scotland by means of diplomacy or coercion. In the 2nd century A.D. the Roman Empire would cease its growth, which began some 700 years earlier.