Frauenwinkel, Protected natural area at Zürichsee lakeshore, Switzerland.

Frauenwinkel is a mire and reed landscape at the Seedamm isthmus in Hurden, part of Freienbach in the canton of Schwyz. Its reed and marsh belt measures about 1 km east to west and 1.5 km north to south, bordered by Lake Zurich to the west, Pfäffikon to the south and the Hurden canal to the north. The protected area also takes in a lake zone of about 3.5 km toward the islands of Lützelau and Ufenau.

Emperor Otto I donated the site to Einsiedeln Abbey in 965 AD, and the abbey still owns it. The first nature reserve was established in 1927; protection followed in 1980 and 1996. Since then the mire landscape and lake zone, including the islands of Lützelau and Ufenau, have been listed as a moorland and fen site of national importance.

The name Frauenwinkel comes from a 965 AD donation by Emperor Otto I to the Einsiedeln Abbey, which still owns the land. The protected site also covers part of the Seedamm archaeological zone, with remains of prehistoric wooden bridges and pile dwellings at Freienbach–Hurden Rosshorn, Freienbach–Hurden Seefeld, Seegubel and Rapperswil-Jona–Technikum. These settlements belong to the 56 Swiss sites of the UNESCO World Heritage Prehistoric pile dwellings around the Alps.

Parts of the area are open to visitors, though some sections are restricted to protect wildlife and plants. Staying on marked paths and following posted guidelines helps preserve the delicate habitats from disturbance.

The area harbors remains of prehistoric pile dwelling settlements that hold UNESCO World Heritage status within an archaeological zone. These submerged communities offer rare glimpses into ancient lakeside life spanning multiple centuries.