Colombier Castle was built in the 11th or 12th century as a fortified tower over the ruins of the Roman villa. It expanded in the 13th Century and by the 16th century had reached its present appearance.
One of the largest Roman era villas in Switzerland was excavated from under the castle in 1840-42 by Frédéric Dubois de Montperreux. It was built in multiple stages between the 1st and 3rd centuries AD into a palatial mansion with a peristyle, at least two baths with mosaics and frescoes and terraced gardens.
In 1806, Colombier Castle was converted into a military hospital. Starting in 1824 it was used by the Federal militias as a parade ground and was converted into a barracks and given an expanded arsenal. In 1877 it became the official barracks of the 2. Division, which later became Field Division 2. In 2003, the Army XXI reforms dissolved the Division and in 2004 the barracks became an infantry training center.
References:The Château de Foix dominates the town of Foix. An important tourist site, it is known as a centre of the Cathars. Built on an older 7th-century fortification, the castle is known from 987. In 1002, it was mentioned in the will of Roger I, Count of Carcassonne, who bequeathed the fortress to his youngest child, Bernard. In effect, the family ruling over the region were installed here which allowed them to control access to the upper Ariège valley and to keep surveillance from this strategic point over the lower land, protected behind impregnable walls.
In 1034, the castle became capital of the County of Foix and played a decisive role in medieval military history. During the two following centuries, the castle was home to Counts with shining personalities who became the soul of the Occitan resistance during the crusade against the Albigensians.