The Koffiemolen is an historic corn mill located on Formerum in the town of Formerum - Terschelling. The mill was built in 1876, and is the only windmill on the Wadden Sea islands of Terschelling. The mill was sold to Jan van Dieren , and is still owned by Van Dieren today. The Koffiemolen was restored in 2002, and is in very good condition. The mill is open to the public, and tours are available upon request.