It is one of three Roman sites in Caerleon, along with the Baths museum and the open-air ruins of the amphitheatre and barracks.

This was built to a design by H.F Lockwood of Hull, a simple box-shaped building of Bath stone.

Its only architectural feature of note was the pillared portico in the Greek Doric style.

Little is known of the original building but it is known to have re-used ship's timbers in its roof and stone details from the Old Market House of Caerleon which had been demolished shortly before.

[2] It is often claimed that the timbers are from HMS Collingwood, although this ship was in service at the time and had no obvious connection to Newport.