Seedamm

Seedamm is the partially artificial causeway and bridge at the most narrow area of Lake Zurich, between Hurden (SZ) and Rapperswil (SG). The Seedamm carries a road and a railway across the lake, with the railway being used by the S5 and S40 lines of the S-Bahn Zürich and by the Südostbahn Voralpen Express.

The Seedam is based on an ice age moraine located between the three Swiss cantons of Schwyz, St. Gallen and Zürich. This morain formed a peninsula protruding from the south shore of the lake and containing the village of Hurden, a small island to the Rapperswil side of the lake, and a section of shallow water dividing Lake Zürich and its upper part (so-called Obersee). The causeway and bridges span this area of shallow water, are 1 kilometre (0.62 mi) in length and carry a road and a railway line. To the east of the modern causeway and bridge, there is the Holzbrücke Rapperswil-Hurden (wooden bridge for pedestrians), built in 2001 as a reconstruction of the first bridge between eastern and western lakesides around 1650 B.C. Situated to the southwest, Frauenwinkel is a mire landscape situated at the Seedamm' area on the easternly Zürichsee lakeshore between Hurden and Pfäffikon, respectively the Lützelau and Ufenau islands.

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