Wägitalersee, Reservoir and lake in Schwyz, Switzerland

The Wägitalersee is a reservoir in the municipality of Innerthal, canton of Schwyz, held back by the Schräh gravity dam, the first dam in the world over 100 metres high. Forested slopes of the Gross Aubrig, Fluebrig and Zindlenspitz descend to the shore, and a hiking and cycling route circles the water.

The lake was created in 1924 when the Schräh dam was built, which submerged the original village of Innerthal. The former villagers then resettled along the new shoreline.

The lake is fished today, and the old bathing and spa hotel that stood in the valley before the dam was built is gone. The flooded village of Innerthal was rebuilt with its church, school and parish house on the present shore. Beat Hüppin's 2016 novel Talwasser takes the dam's construction as its subject.

Several hiking trails run around the lake and lead to various viewpoints. Parking is available, and PostBus connections link the area to the train station at Siebnen-Wangen.

The lake is an important energy source for the region, using its alpine location to generate electricity. Many visitors do not realize that remains of the old village still lie beneath the water surface.