Killarney is a stop on the Ring of Kerry scenic drive, the start and finishing point of the 200-km Kerry Way walking trail, and the gateway to Killarney National Park. For a nice off-road run in Killarney, there’s a series of footpaths starting at the Killarney National Park Visitor Center, exploring the Killarney House & Gardens, heading southwest to Ross Castle and then out to Library Point. The path alternates between open fields, some views of the River Deenagh, and wooded sections.
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Starting at the Visitor Center, explore the paths around the Killarney House & Gardens. Then,  continue on the footpath along the river. It’s 4.5 km to Ross Castle, where you can explore trails around the castle grounds, and then another 2.2 km out to Ross Island as far as Library Point. There are some additional paths on Ross Island.

Add-Ons/Variations. This route overlaps with two trails that are part of Killarney National Park: Knockreer Circular Walk, starting at Killarney House and Gardens, and several trails on Ross Island.