Killarney's biggest attraction, in every sense, is nearby Killarney National Park. The town itself can easily be explored on foot in an hour or two.
On a hilltop 5km west of town, Aghadoe's sweeping views of the Killarney lakes, mountains and Inisfallen Island have made jaws drop for centuries. At the eastern end of the hilltop meadow are the ruins of a Romanesque church and 13th-century Parkavonear Castle. Parkavonear's keep, still standing, is one of the few cylindrical keeps built by the Normans in Ireland.
There's no public transport, but several tour buses stop here.
Feature: Kerry Way
The 214km Kerry Way (www.kerryway.com) is the Republic's longest waymarked footpath. Starting and ending in Killarney, it winds through the spectacular Macgillycuddy's Reeks, Ireland's highest mountain range, before continuing around the Kerry coast through Cahersiveen, Waterville, Caherdaniel, Sneem and Kenmare.
It takes around 10 days to complete the whole route; with less time it's worth hiking the first three days as far as Glenbeigh, from where a bus or a lift could return you to Killarney. Accommodation along the trail is listed on the website. Ordnance Survey 1:50,000 maps 78, 83 and 84 cover the walk.