Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Etang de la Gruere - Etang de la Gruere is a small lake in the Jura range near Saignelegier Canton of Jura Switzerland. The lake and the surrounding bog is a nature preserve. The lake was formed in the 17th century when a dam was built for a mill.
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Natural Place