Evidence suggests that the Town Gaol was located in the cellar of the Guildhall prior to 1769 but once the rear extension was added it was relocated to the rear of the new ground floor.

During the late C18 prisoners carved graffiti into the panelled walls of the gaol room, leaving us a fascinating record of this turbulent time in world history.

By far the most common carvings are of boats and ships, with the vessels and flags depicted suggesting that French and American prisoners of war were once incarcerated.

At a later date steel bands were criss-crossed over the panels, perhaps suggesting that prisoners had tried to escape by removing the wood, and these bands overlay the graffiti. The room was later re-purposed, probably after the Redoubt was built, and the graffiti was lost until the room was refurbished in the 1970s.