Korpinkierros Trail, Haukkalampi (Nuuksio National Park)

Korpinkierros is the longest of the marked loops starting from the Haukkalampi trailhead in Nuuksio National Park, in Espoo, Finland, roughly 35 km from central Helsinki. The circular route is about 8 km and takes around four hours at a relaxed pace. The trailhead is at Haukkalammentie 32, 02820 Espoo. Public transport is the simplest approach: an HSL train (U, E or L) runs to Espoo station, from where HSL bus 245 or 245A continues towards Nuuksio. Visitors can leave at the Punjonsuo stop, about 100 m from the trail link, or at Nuuksionpää, about 2 km from Haukkalampi. In winter the bus service ends at Nuuksionpää, so the walk in is longer. Entry to the national park is free, and current timetables and fares are on reittiopas.hsl.fi.

The terrain is rolling forest with repeated short climbs over rock ridges rather than any long ascent, so total elevation gain stays modest even though the path rarely stays flat. Surfaces alternate between packed forest soil, tree roots and bare granite, which becomes slippery after rain. The route passes through old-growth pine and spruce, which gives fair shade in summer, while the exposed rock sections open up views over forest ponds typical of the Nuuksio plateau. The loop is long enough that it can feel remote despite the proximity of the capital region.

Cooking sites with fire places are available in the Haukkalampi area, and fires are permitted only at marked sites. Visitors should carry their own drinking water, since taking 1 to 1.5 litres is advised, and bring food for a lunch stop. Because this is a loop, there is no formal turn-around point; shorter alternatives exist in the same trailhead area, namely the 4 km Haukankierros and the 2 km Punarinnankierros, and these can serve as a bail-out if weather or fatigue sets in. Trail information and maps are provided by Metsähallitus through Luontoon.fi, and an offline map is worth downloading in advance because mobile coverage can be patchy in the forest.