Walltown was a township in the ancient parish of Haltwhistle and became a separate civil parish in 1866. Walltown ceased to be a civil parish in 1955, but its destinaation has not been given in A Vision of Britain through Time. It is assumed it was absorbed back into Haltwhistle since it is located on the northwestern border of the large parish. However, in Google Earth, Great Chesters is classified under Greenhead.
Milecastle 45 (Walltown) was a milecastle on Hadrian's Wall. Milecastle 45 is located on the top of Walltown Crags. The walls have been comprehensively robbed, and little remains but the robber trenches and turf-covered spoil mounds. The site is clearly visible as earthworks on aerial photographs. Each milecastle on Hadrian's Wall had two associated turret structures. These turrets were positioned approximately one-third and two-thirds of a Roman mile to the west of the Milecastle, and would probably have been manned by part of the milecastle's garrison. (Source: Wikipedia)