The squat brick firehouse with the cupola dominating Market Square was built in 1823 to garage the city's hand-pumped fire engines. After a stretch as a fire museum it was converted in 1991 to a black-box theatre with a downstairs gallery and now hosts local theatre productions, music nights, comedy, and the city's small repertory cinema programme.
Check the schedule before a visit — there's usually something on three or four nights a week. The gallery is free and worth a look during downtown wandering hours.