The Southern Highland Group consists of the Pitlochry Schist Formation overlain by the Loch Katrine Volcanic (or Volcaniclastic) Formation which is in turn overlain by the Ben Ledi Grit Formation. Ben Lomond, Ben Venue and Ben Ledi are all formed from the Ben Ledi grit. Ben Vorlich, Ben Ime and Ben Arthur are all formed from the Beinn Bheula Schist.