Irrsee

The Irrsee (also Zeller See) is the warmest lake in the Salzkammergut and one of the least developed, thanks to protected natural area status that has kept its shoreline largely free of commercial infrastructure. Temperatures reach 26 to 27 degrees Celsius in summer; the lake is shallow and heats fast. Best reached by car from Mondsee or Vöcklabruck. No facilities on much of the shore: bring supplies. Combine with the Irrsee Heimathaus in Zell am Moos for local context.