Siljan Ring Siljan Ring The Siljan Ring () is a prehistoric impact crater in Dalarna, central Sweden. It is one of the 15 largest known impact craters on Earth and the largest in Europe, with a diameter of about . The impact that created the Siljan Ring occurred when a meteorite collided with the Earth's surface during the Devonian period, about 376.8 ± 1.7 Ma. This coincides around the first Devonian extinction, the Kellwasser Event or Late Frasnian extinction at 376.1 Ma ± 1.6 Ma. The effects of the impact can clearly be seen in the bedrock in the area. The Cambrian,
Siljan, Norway parish) is named after the old "Siljan" farm (Old Norse: "Seljur"), since the first church was built there. The name is (probably) the plural form of "selja" which means "sallow tree" or "willow". Prior to 1918, the name of the municipality was "Slemdal". The coat-of-arms is from modern times. They were granted in 1989. The arms show three white saw blades on a green background. It was chosen to represent the timber industry of the municipality. Siljan, Norway Siljan is a municipality in Telemark county, Norway. It is part of the traditional region of Grenland. The administrative centre of the