In the courtyard of the headquarters building is an impressive well, 43 feet deep and 4 feet square, lined with carved stones all the way down. This well yielded a great number of archaeological finds, including wooden comb, sandals, shoes, and arrowheads. A short distance to the east is an Iron Age fort.
The most significant discovery at Bar Hill was a small 2nd-century altar to Silvanus, which is thought to have stood at a shrine just outside the fort. This altar, standing three feet high, is now stored at the Hunterian Museum in Glasgow.
The altar bears an inscription in Latin which translates as "Erected to the God Silvanus by Caristanius Iustianus, praefect of the first cohort of Hamii, in willing payment of a vow."