The remains of Castle Moil (in Gaelic, Caisteal Maol), a three-story stronghold of the MacKinnons dating from the 15th century, overlook the harbour. Tradition has it that there was a much earlier castle on the site, associated with the fourth MacKinnon chief, Findanus, and his Norwegian wife, a princess nicknamed 'Saucy Mary'. It is said that the pair ran a chain across the narrows and levied a toll on passing vessels.

In the late 15th century Clan Mackinnon moved from their earlier base at Dun Ringill, near Elgol, to this castle at Kyleakin. At that time the castle was known as Dun Acainn.

Early in the 17th century the clan moved on and the castle fell into disrepair. All that remains is this ruin, looking from some angles rather like a massive decaying tooth!