Dundrum Castle.

Dundrum castle stands on a hill overlooking Dundrum inner bay and its fine natural harbour with views far out to sea. It was known in Gaelic times as Dun Rury. The earliest parts of the castle date from 1177 when it was built by John de Courcy, although de Courcy built it on the site of an earlier Irish fort known as Dun Rury, traces of the origional earth works are mentioned in Patrick Weston Joyce's book 'A Smaller Social history of Ireland' "The great earthworks belonging to the original dún still remain at the base of the rock at one side" The Normans frequently built their castles on earlier Native Irish fortified sites.

A round keep which was added some time after 1204 is attributed to Hugh de Lacy it encloses an area of two and a half acres.

The castle was besieged by King John in 1210 when in pursuit of Hugh de Lacy, who had abandoned it for Carrickfergus, sometime after 1333 it was in the hands of the Maginnis family, who are thought to have built the stone curtain wall, they held it until 1517 when it was captured by the Earl of Kildare, and again to Lord Deputy Gray in 1538. The Magennises seem to have occupied it between these dates, in 1601 it was surrendered to Lord Mountjoy and granted to Edward Lord Cromwell who sold it to the Blundell Family. The Maginnis took the castle in 1641, but later lost it to Cromwell's force, the castle was partially dismantled when they withdrew in 1652, after which the Blundells returned and built a house in the lower walled enclosure.

The gaunt shell of this 17th century house still stands. Ownership of the castle passed to the Marquees of Downshire when he married a member of the Blundell family, who also had estates at Edenderry County Offaly.