Laacher See

Volcanic caldera lake in Ahrweiler, Rhineland-Palatinate

Laacher See, also known as Lake Laach or Laach Lake, is a volcanic caldera lake with a diameter of 2 km (1.2 mi) in Rhineland-Palatinate, Germany, about 24 km (15 mi) northwest of Koblenz, 37 km (23 mi) south of Bonn, and 8 km (5.0 mi) west of Andernach. It is in the Eifel mountain range, and is part of the East Eifel volcanic field within the larger Volcanic Eifel. The lake was formed by a Plinian eruption approximately 13,000 years BP with a Volcanic Explosivity Index (VEI) of 6, on the same scale as the Pinatubo eruption of 1991. The volcanic discharge observable as mofettas on the southeastern shore of the lake is a sign of dormant volcanism.

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