Waléran, the first Count of Arlon, built a fortified chateau at the top of the town during the 11th century. Along with the town ramparts, this was completely destroyed in 1558 when Arlon was pillaged by the troops of the Duc de Guise. When the Capuchin monks arrivedin Arlon in 1621, they built their abbey on the ruins of the castle.
In 1681 a Vauban-type fortified wall was built transforming the abbey into a citadel. After being the victim of alightning strike in 1719, it was decided to dedicate the church to Saint Donat. The old religious foundation of the Capuchins was finally abandoned in 1796 - Only the church survived and was then restored and renovated during the 20th century.
References:Redipuglia is the largest Italian Military Sacrarium. It rises up on the western front of the Monte Sei Busi, which, in the First World War was bitterly fought after because, although it was not very high, from its summit it allowed an ample range of access from the West to the first steps of the Karstic table area.
The monumental staircase on which the remains of one hundred thousand fallen soldiers are lined up and which has at its base the monolith of the Duke of Aosta, who was the commanding officer of the third Brigade, and gives an image of a military grouping in the field of a Great Unity with its Commanding Officer at the front. The mortal remains of 100,187 fallen soldiers lie here, 39,857 of them identified and 60,330 unknown.