Open water swimming | Trail running | Swimrun

Finnish Lakeland: Sports and nature combined

PURESISU events in the heart of Saimaa. Built on clear waters and forest terrain.

Swimming, swimrun and trail running in the heart of Finnish Lakeland

Every step, stroke and moment in nature contributes to well-being. In PURESISU events, physical activity meets the beauty of nature in Finnish Lakeland, in the landscapes of Savonlinna and Punkaharju.

Event series: Puruvesi Swim (27 June), Punkaharju Swim (22 August 2026), Run Forest Run trail run and Punkaharju Swimrun on Finnish Nature Day (29 August 2026). See presentations below.

PURESISU events:

Puruvesi Swim 27.6.2026

Sport: Open water swimming
Route: Around the Petrisaari nature reserve in the exceptionally clear waters of Lake Puruvesi
Distances: 2.5 km, 5 km, 10 km

Punkaharju Swim 22.8.2026

Sport: Open water swimming
Route: In the clear waters of Punkaharju, part of one of the world’s oldest nature reserve areas
Distances: 1 km, 2 km, 4 km

Run Forest Run 29.8.2026

Sport: Trail running
Route: Through the Punkaharju research forest and nature reserve, featuring Finland’s tallest tree and other unique natural highlights
Distances: 10.2 km, 17.7 km

Punkaharju Swimrun 29.8.2026

Sport: Swimrun
Route: Along forest trails and ridge landscapes, with swimming sections in the clear waters of Lake Puruvesi and Lake Pihlajavesi
Distances: 10.5 km (1.9 km swimming) and 20.4 km (3.2 km swimming)

PURESISU: From outdoor enthusiasts to outdoor enthusiasts

We spend time in swimming pools, gyms and sports halls.

But not every place for movement needs to be built, treated or surfaced.

In nature, uphill and headwinds build strength, downhill develops coordination. Jumps, turns and changes of rhythm break monotony. Your whole body works.

Scents, colours, sounds and wildlife keep you engaged. Time passes without you noticing. Outdoor exercise also clears the mind.

That is PURESISU.