One of the most well-known building in the valley of the river Geul is probably the Volmolen just outside the village of Epen. The mill was part of the broadcloth industry in Vaals. Because of the location of the mill on the Geul, there was an abundance of water available for vollen - that’s why the mill is named Volmolen - the fulling of the wool. There was not such a large amount of water in the vicinity of Vaals.

The history of the Epener mill dates back to the 17th century. In 1680 there was already talk of an oil mill. Later it is said to have been used as a bark mill. It was only in the last decades of the 18th century that it became a fulling mill.

The urine and rancid butter needed for the fulling process was discharged into the river Geul after use. So it is not strange that the Volmolen was built outside the village centre of Epen. The complex is situated between the Geul and a dug mill brook. Water is pumped up into the brook to increase the decay of the water at the waterwheel. The buildings, a mill house and a farm with attached barns, surround a courtyard. The walls of the buildings are built in various types of locally broken stone.

In 1872 the mill was converted into a flour mill. After several renovations and restorations the Volmolen was put into a flour mill in 1977. The mill is now owned by the Vereniging tot Behoud van Natuurmonumenten (Society for Preservation of Nature Monuments in the Netherlands). A foundation for the exploitation of the mill has a contract with a group of bakers for the supply of flour.