La Fontaine Castle

La Fontaine Castle, also known as Palais Mansfeld, was a magnificent residence located in Clausen, Luxembourg. Construction began in 1563 under the direction of Peter Ernst I von Mansfeld-Vorderort, the Governor of Luxembourg, and continued until his death in 1604. The architectural style blended late Gothic elements with Renaissance influences, likely designed by an architect from the Netherlands associated with Hans Vredeman de Vries. Some historical accounts suggest the design was inspired by Château Fontaine near Brussels. The massive structure featured a façade approximately 200 meters long and was strategically set against surrounding rocks to maximize space for its elaborate gardens.

The estate held significant historical importance as a symbol of Mansfeld's power and his deep interest in antiquity. The grounds included a five-kilometer walled hunting park and sophisticated water features drawn from the River Alzette, such as a famous fountain depicting Venus riding a whale surrounded by spraying animal statues. The gardens were adorned with numerous Roman statues discovered in nearby Arlon. Despite its grandeur, the castle fell into ruin shortly after Mansfeld's death. His heir, Infanta Isabella, rejected the property due to heavy debts, and the valuable art collection was transported to Madrid. The building subsequently decayed and was ultimately destroyed during the French siege of Luxembourg in 1684.

Today, almost nothing remains of the original structure above ground. Knowledge of its former glory relies primarily on period paintings by artists like Georg Braun and Joachim Laukens, as well as written descriptions from the era. While the main buildings have vanished, archaeological excavations of the garden fountains and their remains have been ongoing since 2003. The site currently serves as a historical landmark where visitors can learn about this lost architectural marvel through historical records and ongoing research rather than standing structures.