The remains of the roman Castle can be visited
Roman Milecastle 48

Roman Milecastle 48, also known as Poltross Burn Milecastle, was once part of Hadrian's Wall. It is located near the village of Gilsland in Northumberland, England.
History+
The site was first excavated in 1886 by R. S. Ferguson. Between 1909 and 1911, J. P. Gibson and F. G. Simpson continued the work, followed by D. Charlesworth in 1965 and 1966. These excavations uncovered the milecastle's gates and the lower steps of a staircase that once led to the ramparts of Hadrian's Wall. An oven was also discovered in the northwestern area. Long barrack blocks flanked the central area, likely constructed in multiple phases.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Ozymandias
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 54.9890, -2.5735