| Mattmark dam | |
|---|---|
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  Mattmark dam  Mattmark dam  Mattmark dam | |
| Location | Saas Valley, Valais |
| Coordinates | 46°2′17″N 7°57′36″E / 46.03806°N 7.96000°E |
| Type | reservoir |
| Catchment area | 37.10 km2 (14.32 sq mi) |
| Basin countries | Switzerland |
| Max. length | 3.2 km (2.0 mi) |
| Surface area | 1.76 km2 (0.68 sq mi) |
| Max. depth | 93 m (305 ft) |
| Water volume | 100 million cubic metres (81,000 acre⋅ft) |
| Surface elevation | 2,197 m (7,208 ft) |
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Mattmark dam is a reservoir in the Saas Valley of the Canton of Valais, Switzerland. The Mattmark dam was built from 1960 to 1965. The lake's surface area is 1.76 km2 (0.68 sq mi).
The lake lies at a height of 2,197 metres above sea level, between the massifs of the Rimpfischhorn and Stellihorn. The highest peak visible from the lake is the Strahlhorn (4,190 m).