The lake's high temperature is due to its relatively small surface area, low inflow of cold mountain water, and a sheltered position.
Klopeiner See is considered a 'drinking water quality' lake due to its superior ecological state.
The lake features a boardwalk and promenade system that encircles much of the perimeter for pedestrian access.
It is a popular location for 'Seerosen' (water lilies), which thrive in the calm, clean waters.
The region experiences higher sunshine hours than most other parts of Austria due to its location south of the Karawanks mountain range.
Lake Klopein is one of the warmest Alpine lakes in Europe, with summer water temperatures frequently reaching up to 28 degrees Celsius. Located in the Carinthia region, the lake is situated at an elevation of 446 meters above sea level. It is biologically classified as oligotrophic, meaning it has high water clarity and low nutrient content, making it safe for drinking quality standards. The shoreline is mostly accessible through private lidos and hotels, though public swimming areas exist. The lake covers approximately 1.1 square kilometers and reaches a maximum depth of 48 meters. The surrounding area is heavily integrated into local tourism infrastructure, focusing on cycling and summer water sports. As of July 2026, the lake remains a primary destination for family-oriented recreational swimming in Austria.
The wooden boardwalk along the northern shore during sunset.
Book accommodation with private beach access to avoid the crowds at public lidos.
Bring a bicycle to navigate the flat, well-maintained paths circling the lake.
Pack polarized sunglasses to better view the clear, underwater vegetation from the boardwalks.
Do not attempt to swim from private docks belonging to local hotels or houses.
Recreational water activities are primarily available from late spring through early autumn.
Respect private beach boundaries; many areas are restricted to guests of specific local hotels.
