Breachacha Castle is either of two structures on the shore of Loch Breachacha, on the Inner Hebridean island of Coll, Scotland. The earlier (also called Old Breachacha Castle) is a 15th-century tower house that was a stronghold of the Macleans of Coll, the island having been granted to John Maclean in 1431. This castle was superseded by a new dwelling in 1750 (see below) but continued to be occupied for a time, falling into a ruinous state only in the mid-19th century. Although work was performed in the 1930s to prevent further dilapidation, the castle was restored to livable condition only in the 1960s, by Major N. V. MacLean Bristol.