A fragment of the city wall which once guarded the Roman city of Londinium, capital of the province of Britannia, can still be found in the confines of the Tower of London.
William the Conqueror is said to have built the Tower on the site of an old Roman fort. No doubt the city wall will have led up to this Roman army base.
Just outside the central White Tower of the fortress stand the remains of the wall. The line of red tiles, so typical to many Roman buildings, can clearly still be seen.