Dundonald Castle is located on a hill overlooking the village of Dundonald (Scottish Gaelic: Dùn Dhòmhnaill) which is south from the A579 road and between Kilmarnock (Cille Mheàrnaig) and Troon (An Truthail / An t-Sròn) in South Ayrshire, Scotland ( Siorrachd Inbhir Àir a Deas, Alba). The remains of Dundonald Castle, which was a three storey high fortified tower house, stand on the site of an Iron Age Hillfort. Three subsequent castles have stood on the hill but nothing survives from the first twelfth century earthwork and timber structure.
There are some remains of the thirteenth century castle including the well and part of the tower. The castle that can be seen today is the third fourteenth century castle with later fifteenth century extensions. The third castle was built by Robert Stewart, who became King Robert II of Scotland in 1371. It was used as a royal residence by Robert II and his son Robert III. The castle is open to the public and there is a Visitor Centre at the site and details are available on the link below.
Link: Dundonald Castle and Visitor Centre.
Image: Dundonald Castle, old photograph dated 1903.