Drochil Castle is a ruined castle in the Scottish Borders. It is located above the Lyne Water, 10 kilometres (6.2 mi) north-west of Peebles, and 8 kilometres (5.0 mi) south of West Linton. James Douglas, 4th Earl of Morton, Regent of Scotland, started building Drochil Castle in 1578, three years before his execution by King James VI. It was no more than half built on his death, and was never finished.