Laacher See

Laacher See (literally: Lake Laach; ) is a volcanic caldera lake located in Rhineland-Palatinate, Germany.
The diameter is 2 km, and it is located 24 km from Koblenz, 8 km from Andernach and the Rhine River, and 37 km from Bonn. Its last volcanic eruption, which was a Plinian eruption, was around 11,000 years B.C., with a Volcanic Explosivity Index (VEI) of 6, having the same magnitude as the Plinian eruption of Mount Pinatubo in 1991. It is part of the mountainous Eifel region, and the East Eifel Volcanic Region, which was formed after the collision of the African and Eurasian continents millions of years ago. To the west of the lake is the Maria Laach Abbey, built in 1092 by Henry II of Laach, Count of the House of Luxembourg.