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Länggrien

Länggrien (also known as Aareinseli) is an island in the River Aare, located in the canton of Solothurn. The island has a maximum length of 600 metres and a maximum width of 270 metres. Its highest point is 428 metres above sea level, a few metres above the river level. The minimum distance from the shore is about 50 metres.

Politically the island belongs to the municipality of Selzach in the district of Lebern.