The remains of the roman Castle can be visited
Roman Milecastle 39

Roman Milecastle 39, also known as Castle Nick, is a well-preserved Roman small fort that forms part of Hadrian's Wall in Northumberland, England.
History+
The site was first cleared in 1854 and extensively excavated between 1908 and 1911, and again from 1982 to 1987. These excavations revealed the foundations of a long-axis milecastle with a Type II gateway. In the southeastern area, archaeologists discovered a stone oven, while in the southwestern part, a rectangular building with a sunken floor and Roman artifacts was found. The milecastle appears to have been occupied until the late 4th century.
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: 55.0036, -2.3757