Roman Fort Gariannonum

The name Gariannonum is derived from the river Gariennus, as it was referred to by Ptolemy in his Geographica in the 2nd century AD. The fort, along with Caister-on-Sea, served to protect the river mouth. It housed the Equites Stablesiani Gariannonensis, a unit of Roman auxiliary troops under the command of the Comes litoris Saxonici per Britanniam. Although its layout still reflected the style of the 2nd century, the fortress was later modernized with ten horseshoe-shaped defensive towers, which were added to the walls at regular intervals.