The Vestingmolen Bourtange is a replica of an old post mill from Ter Haar. The mill is a part of a recent reconstruction of a fortress, and was built in 1980. The builders had considered moving the original mill, but decided that a replica would be an easier, and safer solution. The current millers are Dhr’n H. Forests and R. Pepping. The mill is used to grind corn, and is open to the public every Saturday during the summer months.