Pont Mynwy Codwyd Pont Mynwy tua 1270 i warchod y dref. Hi yw'r unig bont o'r canoloesoedd, a phothdy arni, sydd ar ol ym Mhrydain. Bu'r porthody yn ei dro yn dollborth, gwarchodfa, carchar a chartref.

English translation: "Monnow Bridge built circa 1270, as a town defence, is the only surviving medieval bridge in Britain with the gate tower standing on the bridge. The gatehouse has served as a toll-house, guard room, gaol and dwelling house. "