One of Ulster's most evocative medieval ruins, Dundrum Castle was founded by the legendary Norman adventurer John de Courcy following his invasion of Ulster in 1177. The site occupies the summit of a rocky hill commanding fine views over Dundrum Bay and the plains of Lecale, con trolling access into east Down from the south. De Courcy's original castle may have had defences of earth and timber, but it is probable that the stone curtain wall of the upper ward was built as early as the 1180s. As with other early enceinte (enclosure) walls, there were no towers, but defence was evidently aided by covered walks with machicolations along the outside wall-head. An early timber hall may have been sited near the keep, where there is a double-latrine in the curtain wall.
In 1204 de Courcy was expelled from Ulster by Hugh de Lacy who proceeded to strengthen the castle by build ing the massive round keep, probably employing master masons from the Welsh Marches, where such keeps were then popular. Although much of the second floor of this keep was largely rebuilt in the fifteenth century, it is clear from the survival of the old fireplace flue and spiral stair that it originally stood at least three storeys high. The base ment was used for storage and had a cistern below; the first, or entrance, floor, with its large fireplace and hand some windows, appears to have been the great chamber for the lord's day-to-day living, while the floor above would have housed his private chamber.
The castle was captured by King John in 1210 and remained Crown property until de Lacy was allowed to return to his Earldom in 1226. It was probably during de Lacy's second tenure as Earl of Ulster (1227-43) that the twin-towered gatehouse, similar to the one at Pembroke Castle, was inserted into the curtain wall. It has a lopsided design with only one projecting tower to protect the approach along a narrow ramp from the south-west.
The stone curtain wall of the outer bailey is likely to have been built by the Maginnis family, who seized Dundrum in the late fourteenth century and held it intermittently until finally expelled by Lord Mountjoy in 1601. It was made over to Lord Cromwell in 1605 and sold to Sir Francis Blundell in 1636. The Maginnis family retrieved Dundrum in 1642, but later lost it to the Parliamentarians, who dismantled the castle in 1652 after they withdrew their garrison. After 1660 the Blundells returned and built a gabled L-shaped mansion in the south west corner of the outer bailey. This dwelling was ruined by the time the property passed to the second Marquess of Downshire in the early nineteenth century, though the trees on the hill were probably planted at this time. The castle and grounds were placed in State Care by the seventh Marquess in 1954.
Located just above Dundrum village.
NGR: J 404370.
State Care Monument. Open April to September; other times by request.
Small admission fee charged.