The Grolloo Mill was built in 1930. It is a small watermill, with short, wooden sails. The mill is still in use today, and is used to drain the Grollooerveen – a large peat complex which is home to a variety of rare plants and animals. The peat complex is only accessible on foot, or by bicycle, cars and other vehicles are no longer allowed on the moor, as they could cause damage to the peat.