Ardencaple Castle, also known as Ardincaple Castle, and sometimes referred to as Ardencaple Castle Light, is a listed building, situated about 1 statute mile (1.6 km) from Helensburgh, Argyll and Bute, Scotland. Today, all that remains of the castle is a tower, perched on the edge of a plateau, looking down on a flat tract of land between it and the shore of the Firth of Clyde.