From Killarney take the Kenmare road as far as Muckross and then take the first sharp left after Molly Darcy's pub. Drive uphill to a fork in the road with a sign for Mangerton. Take the road to the right and drive along this road until you see a rough track heading off to the left (V984 848 A) just after a track on the right. There's plenty of parking here along the road or at the start of the track.

This track will take you to the Devil's punchbowl. The start of the walk presents you with a gradual climb as the track meanders either side of a largely dry riverbed. The Lakes of Killarney emerge spectacularly on your right as you gradually gain height. The track winds on upwards until you eventually reach the punchbowl. Walk to the back of the punchbowl and follow the ridge north to the summit of Mangerton north, a grassy area with a small pile of stones.
Drop down east to the col, with a curious fenced off square, before the brief ascent to Glencappul Top. Linkback: https://mountainviews.ie/summit/111/comment/4871/