This modest yet striking 15th-century tower house served as part of the prebend of St Patrick’s Cathedral, connecting it to the ecclesiastical power structures of medieval Dublin. The castle’s appearance was captured for posterity in a detailed 1763 drawing by Gabriel Beranger, which remains one of our best visual records of this lost structure.

The castle’s design reflected the defensive needs of its era whilst incorporating some unusual architectural choices. Built as a small, square tower house, it featured two corner towers positioned diagonally opposite each other; one of these housed the spiral staircase. Rather unconventionally for such fortifications, the entrance was located within the southwest stair tower itself, protected from above by machicolations that allowed defenders to drop projectiles on unwelcome visitors. The structure rose three storeys high, with a vaulted basement providing secure storage and battlements crowning the top for defence.

Though Tymon Castle survived nearly five centuries, changing times and urban development sealed its fate. Like many of Ireland’s smaller medieval fortifications, it fell victim to mid-20th century progress when preservation wasn’t yet a priority. Today, only historical records and Beranger’s careful illustration allow us to imagine this once-prominent landmark that linked medieval Dublin’s religious and defensive landscapes.