Castle Semple

Castle Semple are ruins of a fortress that once sat on the eastern shore of a loch in Renfrewshire, with surviving outbuildings and remnants of garden walls from centuries of occupation. The site shows changes across different periods, from medieval structures to later additions made by successive owners.

The fortress was built in the 1500s as a successor to an earlier stronghold and took its name from John Sempill, 1st Lord Sempill, who developed the estate. A major transformation occurred in the 1730s when a new owner replaced the old structure with a fashionable country house reflecting the architectural trends of that era.

Colonel William McDowall replaced the original structure in 1735 with a Palladian country villa, marking an early example of this architectural style in Scotland.

The buildings on the site are in private ownership and not open to visitors, but the exterior and grounds can be viewed from public paths and nearby roads. The location is in a rural area and accessible on foot from neighboring villages.

A copper cannon bearing Scottish arms was submerged in the adjacent loch for centuries before being recovered and kept on the grounds. The artifact carries initials linked to the family who once owned the estate.