Lockne is a meteorite crater, located approximately 21 km (13 mi) south of the city of Östersund in northern Sweden. It has been suggested that it is a doublet with the nearby smaller Malingen Crater, 16 km apart. Computer simulations suggest that the asteroid that created the Lockne crater was some 600 meters in diameter, and the one that carved out Malingen crater was about 250 meters across.^[2]

• http://en.wikipedia.org/wiki/Lockne crater