The castle, situated on a headland overlooking Loch Ness, is one of the largest in Scotland in area. It was approached from the west and defended by a ditch and drawbridge. The buildings of the castle were laid out around two main enclosures on the shore. The northern enclosure or Nether Bailey includes most of the more intact structures, including the gatehouse, and the five-story Grant Tower at the north end of the castle. The southern enclosure or Upper Bailey, sited on higher ground, comprises the scant remains of earlier buildings.