The lake basin was carved out by the Drau glacier during the last ice age.
The Carinthian Summer (Carinthischer Sommer) festival has been held at Ossiach Abbey since 1969.
Ossiach Abbey was founded by Benedictine monks in the 11th century.
The lake acts as a significant thermal reservoir, which helps moderate local climate conditions.
The Gerlitzen mountain, overlooking the lake, is a prominent launch site for paragliding.
The lake features a unique 'Lake-Round' cycling path that is largely flat and suitable for families.
The water temperature in mid-summer is consistently among the warmest in Carinthia.
Lake Ossiach is the third-largest lake in the Austrian state of Carinthia, spanning approximately 10.5 square kilometers. It is located at an altitude of 501 meters above sea level and reaches a maximum depth of 52 meters. The lake is fed primarily by the Tiebel stream and its water quality is noted for being of drinking-water standard, often reaching summer temperatures of 26°C. The lake is bordered by the Gerlitzen mountain to the north and the Ossiach Tauern range to the south. Several villages sit along its perimeter, including Ossiach, Annenheim, and Steindorf. The area is a hub for water sports, cycling, and hiking, with a well-maintained 27-kilometer trail encircling the lake. It is renowned for hosting the Carinthian Summer music festival, which utilizes the historic Ossiach Abbey as a primary venue. The lake is part of a larger resort region integrated with the Gerlitzen Kanzelbahn cable car system.
The viewpoint from the Gerlitzen peak looking down over the full length of the lake.
Use the Ossiach See ferry service to navigate between villages rather than driving, as parking can be limited during peak season.
Pack a portable seat cushion if attending outdoor concerts at the Abbey, as seating can be rigid stone or metal.
Explore the southern shore paths for quieter, less crowded swimming spots compared to the busier northern resort areas.
Avoid relying solely on GPS for finding parking in small villages, as narrow lanes often restrict access for large vehicles.
Water-based activities and ferry services are strictly seasonal, operating from late spring through early autumn.
Respect local noise ordinances near residential areas; swimming is prohibited in designated boat traffic zones.
