Lake Zurich is divided into two parts by the dam between Rapperswil (SG) and Pfäffikon (SZ). The eastern half is called “Obersee”. It has a total area of 88.17 km² and measures 3.85 km at its widest point. At the western end of the lake is Zurich, Switzerland’s largest city. Numerous cruise vessels and a regular ferry service operate on the Lake. There are countless swimming areas lining its shores.