Castle Altenbroek, 18th-century castle in Voeren, Belgium

Castle Altenbroek is a white-plastered manor in the Noor valley northeast of 's-Gravenvoeren. Its oldest part is an 18th-century rectangular west wing; the brick north wing dates from around 1775 and was originally a sheep barn with a gable stone showing a sheep and the year 1809. The L-shaped plan was first recorded in 1904, and a U-shaped farmyard with a gate in the east wing lies to the south. The facade has a raised stone terrace with steps and a balustrade, a veranda on slender columns, sash windows, a white bargeboard with pointed pendants, a slate roof, a brick chimney and a square tower.

The name Broek, meaning marshy land, appears around 1300 as Broeke bi Voeren; in 1314 Jan van Voeren is recorded as lord of Broek, a fief of the County of Dalhem. The castle passed through the Melcops, Holset and De Berghe families before Pierre Joseph de Schiervel acquired it in 1790 by marriage. The oldest wing dates from the 18th century, and the north wing was built in brick around 1775.

The name Broek, or Brook locally, means marshy land and appears as Broeke bi Voeren around 1300. The estate became Altenbroek through the Hoen family, while their newer property became Hoensbroek. Since 2018 a company has run the estate as a hotel, wedding and business venue, with a restaurant in the orangery of the castle farm.

The estate is reached by a drive off the road, with the castle set in the Altenbroek nature reserve and its park of ponds and three springs, including the Sint-Lambertusbron. The farmyard lies south of the castle, U-shaped with its open side to the north, entered through a gate in the east wing. The restaurant occupies the orangery of the castle farm.

A shepherd's shed on the grounds contains a carved stone dated 1809 with a sheep relief, marking the property's agricultural roots. This crafted stone reveals how important livestock raising was to the estate's identity and daily operations.