The Haelense Beek has a length of 11 km and is historically of great importance because of the castles that lie along it. The Beegderheide is an area with a wide variety of open heathland and enclosed forests with a large number of small and large fens. The Exatenbosch and the stream valley of the Haelense Beek together form an estate around Exaten castle. Sights include the Aurora Mill, Baexem Castle, Exaten Castle, Groot Buggenum Castle and the Grathemer watermill. The Aurora Mill is a standard mill built in 1845 and rebuilt in 1971. Baexem Castle was first mentioned in 1244, the current buildings date from 1676, the wings were added in the 18th century. Exaten Castle is a building from the early 18th century. The building is enclosed in a complex of 19th century buildings currently belonging to the COA. On the site are the remains of the fortified house De Borg, which may have played a role in the history of the Exaeten monastery in the early Middle Ages. Groot Buggenum Castle was built in 1889 on the foundations of a much older castle. After being seriously damaged in the Second World War, the castle fell into increasing disrepair. Architect Düsseldorf professor H. Hentrich bought the land and what was left of the castle and restored it entirely according to his own wishes. The result is a truly fantastic building. The path that is followed from Grathem is named after the architect. The Grathemermolen is a water mill with a flour mill function, the conversion dates from 1874. Grathem already had a water mill in the 14th century.