Milecastle 51

Milecastle 51 (Wall Bowers), one of the milecastles on Hadrian's Wall, is situated to the west of Birdoswald fort (OS grid reference NY 592 654), at the point where the Stone Wall rejoins the line of the Turf Wall.

Although not now visible, excavation showed that it has two internal stone barracks buildings. It has Type III gateways. It lies 1501m west of Milecastle 50 and 1484m east of Milecastle 52.

The stone milecastle replaced its underlying predecessor, Milecastle 51TW on the Turf Wall.

Milecastle 51 was excavated in 1895.