Kilclief Castle (Irish: Caislean Cill Cléithe) is a tower-house castle beside Strangford Lough and 2.5 miles (4 km) south of the village of Strangford. Kilclief is a hamlet of historical value on the Strangford to Ardglass road. This kind of tower-house is sometimes called the gatehouse type, because of its similarity to a castle gatehouse. It is among the oldest tower houses in Lecale. Kilclief Castle tower house is a State Care Historic Monument in the townland of Kilclief, in Down District Council area, at grid ref: J5972 4575
The castle is tall with four floors. The first floor is vaulted in stone, with two projecting turrets. One (to the south-east) contains a spiral stair and the other (to the north-east) a series of garderobes (latrines) with access from three of the four floors. These projecting turrets are joined at roof level by a high machicolation arch[3] covering a drop-hole for dropping missiles on unwelcome visitors below. There are stepped battlements. As at Jordan's Castle, the ground floor chamber has a semicircular barrel vault built on wicker centering. On the second floor a 13th-century coffin-lid from a nearby church was reused as a lintel for the fireplace. The two-light window in the east wall is a modern reconstruction based on a surviving fragment.
The castle is now in state care. A board outside the castle tells visitors where to obtain a key should they want access. Guided tours are available in July and August.
Information taken from: https://en.wikipedia.org/wiki/Kilclief_Castle