O'Sullivan's Cascade Waterfall in Killarney National Park is a hidden gem that must be experienced! Found deep in the heart of Tomies woods or accessed via boat, this waterfall rivals Torc Waterfall for beauty and has a fun legend to go along with it. According to local myth, this spot was once owned by Fionn MacCumhal and whiskey rather than water flowed from it. O’Sullivan of Tomies is said to have been the only one brave enough to stand up to Fionn MacCumhal and shared a drop of the delightful whiskey.