|Part of the Roman Fort Wall and Bastion 14, London Wall.|
During the 2nd and 3rd centuries, the Romans decided to fortify Londinium, but historian are unsure as to why. They began by thickening the walls of the existing fort and building a wall, which was some 3 miles long, between 8 and 10 feet in depth and up to 20 feet high. There were also over 20 towers, spread at regular intervals. When completed, it was discovered that the wall left the riverbank undefended, which resulted in Saxon pirates raiding he town on numerous occasions. The remedy was to extend the wall to the river.
Following the departure of the Romans, in the 5th century, Londinium became a derelict ghost town. Remaining empty for nearly 300 years, the walls began collapse as nature gradually took over the city. Although, from about 500 AD, there was an Anglo Saxon settlement near Aldwych, called Lundenwic, this was outside of the Roman Walls. By 680, Londinium's port was in use, once again, but it wasn't until the late 880s that Londinium was resettled and, by about 950, its walls were repaired.