Milecastle 45 (Walltown) was a milecastle on Hadrian’s Wall. The mile fort is located on the highest point of Walltown Crag and is a long-ax type. Due to the complete destruction of its walls by stone robbery, little can be seen of it (some moats and elevations). The outlines of the fort can otherwise only be seen clearly in aerial photographs. A few blocks of stone from one of the castle gates are built into a wall at the back of a cattle trough east of Walltown Farm.