[3] The presence of forward-projecting towers with rounded corners is thought to be good evidence for a construction date contemporary with other Saxon Shore forts such as Burgh Castle and Othona.

[6] According to Bede, a place called Dommoc often linked with Dunwich on the Suffolk coast was the seat of East Anglia's first bishop, Felix of Burgundy, in the 7th century, from whom Felixstowe takes its name.

There is some evidence that Walton Castle was the location of Dommoc, where there appears to have been a church dedicated to St Felix inside the walls in the 12th century.

[8] The walls of the Roman fort survived this demolition, and the plan of 1623 shows ruins in the northeast corner which presumably were the remains of the castle.

In Kirby's Suffolk Traveller (2nd edition, 1754) it is stated that around 1740 the west wall of the fort was still standing, but that by 1754 "the Sea hath washed away the remainder of the Foundation.

"[4] When Francis Grose published his The Antiquities of England and Wales in 1786, he included a picture drawn in 1766 which shows the slumped ruins of the wall lying on the beach below the cliff.

[4] In the modern era, it is said (correctly) that remnants of the walls can still be seen at some distance from the beach during exceptionally low tides at Felixstowe.