Thalwil is a municipality and town in the district of Horgen in the canton of Zürich in Switzerland. In addition to the town of Thalwil, the municipality includes the village of Gattikon.

Lake Zurich is a lake in Switzerland, extending southeast of the city of Zürich. Depending on the context, Lake Zurich or Zürichsee can be used to describe the lake as a whole, or just that part of the lake downstream of the Seedamm at Rapperswil, whilst the part upstream of Rapperswil may be called the Obersee or Upper Lake.