The fort at High Rochester (Bremenium) in Northumberland was one of the most northerly outposts of the Roman Empire. The inscription, now in the Great North Museum, was discovered near to the east gate of the fort c. 1776 (RIB 1284). It was then displayed in Alnwick Castle.
The Latin text records work by a unit, vexillatio, of the 20th Legion Valeria Victrix. The inscription is flanked by figures of Mars and Hercules. Below appears to be a boar, the emblem of the legion.
A building inscription for a vexillatio of the 6th Legion Pia Fidelis is also known from the site (RIB 1283).
These two units may have been posted here, not necessarily simultaneously, to reinforce the northern frontier.