The Guildhall on Church Street has been the seat of the Harwich town corporation since the eighteenth century — a sober brick-and-stone building with a small council chamber upstairs and an arcaded ground floor that originally housed the town's lock-up. The interior is unusually well preserved: oak panelling carved with prisoners' graffiti from the 1700s, a courtroom in continuous use until the 1960s, and a small collection of civic silver and mayoral portraits.
The Harwich Society runs tours on Saturday afternoons in summer; the building is otherwise opened by appointment. The graffiti alone — names, dates, sailing-ship sketches, the occasional defiant verse — is worth a slow look.