La Rosiere Castle (Grolley)

In the 12th century, the lords of Grolley were mentioned several times in the registers of donations from Altenryf, particularly as benefactors of the monastery, for example Cono von Groslerio in 1158, Dominus Petrus von Groslerio in 1178, and Hendricus Meilen von Grolers in 1180. However, it is very unlikely that the Grolley themselves owned a castle, as there is no evidence for this. Rather, it is believed that these lords and knights had their residence in nearby Rosières.

The religious congregations seemed to find the location of Rosière suitable. The Carthusians stayed in its castle for two years. One of them was named Dom Léon Marie Guérin, the coadjutor of Valsainte.

Another was named Dom Clixte, a former cavalry captain who had participated in the heroic service of the Cuirassiers in the Battle of Reichshofen in 1870. The latter died in 1904 in Rosière and was buried near Grolley. This castle was occupied by Mariannists between 1944 and 1947. It was acquired and converted from 1966 for the benefit of retirees (Parish Cooperation of Christ the King).