Comyn’s Castle is an interesting site, being a motte which deviates from the normal style. It consists of a D-shaped mound protected by double ditches.
The inner ditch is around 1.5m deep, while the outer ditch is around 2.0m to 3.0m deep. They protect the north and east side of the site, with the south and west site defended by naturally-sloping ground.
The unusual form of the motte suggests its origins may pre-date the 11th century date when a Norman castle is likely to have been established. The lands of Kilbride were originally owned by the Norman de Valognes family. Upon the marriage of Isabel de Valognes to David Comyn in the early 13th century the estate came into the possession of the Comyn family.
One of their descendants, John Comyn, Lord of Badenoch (the Red Comyn), was the son of John de Balliol’s sister, so naturally he supported Balliol’s claim to the Scottish throne. This put him at odds with the rival claimant Robert the Bruce, and in 1306 John Comyn was murdered by Bruce.
Bruce confiscated the Comyn lands and gave them to his son-in-law, Walter Stewart. In 1382 the former Comyn estates were granted to the Lindsay family by King Robert II, in recognition of the help of the Lindsays in the murder of John Comyn.
Archaeological investigations suggest that the castle was destroyed in either the late 14th or early 15th century. This ties in with when the Lindsay family took over the estates, and may suggest that they started work on a new building at nearby Mains Castle around this time, robbing stone from Comyn’s Castle.
Only the mound and parts of the ditches are now visible, the north side of the outer ditch having been filled in.