Lac de Sylans is a lake at Le Poizat in the Ain department, France.
It is significant for the ruins of one of the 19th century's largest ice harvesting factories and the occasional outflow of water in two directions.
Wikipedia https://en.wikipedia.org/wiki/Lac_de_Sylans
Address 01130, France
Coordinates 46°9'40.19" N 5°39'45.973" E