Margaret's Castle

Margaret's Castle is a historic tower house located in the town of Ardglass within County Down, Northern Ireland. Constructed during the 15th century, this small fortification originally stood at least three storeys high, though only two levels remain today. The structure features a rectangular design with a vaulted ground floor and distinctive projecting turrets along the north-west wall. Architectural details include a spiral stairway housed within the west turret and a doorway between the turrets that was historically protected by a murder-hole, highlighting its defensive origins.

The site holds significant historical value as one of at least six castles that once fortified Ardglass, a town that served as a crucial medieval port. Today, ruins of four of these strongholds, including Margaret's Castle, Jordan's Castle, Cowd Castle, and Ardglass Castle, can still be viewed in the area. Margaret's Castle is officially recognized as a Scheduled Historic Monument under the care of local heritage authorities. It stands as a testament to the region's turbulent past and the strategic importance of the Down coastline during the Middle Ages.

Currently, the castle exists in a ruined condition but remains an accessible landmark for visitors interested in Northern Ireland's architectural heritage. Its preservation status ensures that the remaining masonry and structural features are maintained for public education and tourism. As part of the Newry, Mourne and Down District Council area, the site contributes to the rich tapestry of historic monuments in County Down, offering a tangible connection to the 15th-century landscape of Ardglass.