Château fort de Lourdes

Roman-era remains — fragments of sculpture, votive altars and the foundations of ancient walls — came to light during 19th-century military engineering works, which nonetheless destroyed most of what survived; the finds are exhibited on site. Charlemagne besieged the fortress in 778, and by the 11th and 12th centuries it served as the residence of the Counts of Bigorre; the fortifications standing today rest on foundations from that period.

The castle passed to the Counts of Champagne, who were also kings of Navarre — in the 13th century by one account, the 12th by another — before coming under the French crown under Philippe le Bel. The Treaty of Brétigny of 1360 ceded it to the English; the order handing it to Raymond de Castelbajac, lord of the place, is dated 23 November 1361. It returned to France at the start of the 15th century after two sieges.

The castle was reinforced again in the 13th and 14th centuries, including construction of its keep. A tall residential tower is credited to Gaston Fébus, count of Foix-Béarn, in the late 14th century.

From 1590, under Henri IV, the castle served as a prison; it became a royal prison in the 17th century and then a state prison after the Revolution, a role it kept until the start of the 20th century. It also had a spell as a barracks before, in 1921, Louis Le Bondidier and his wife Margalide established the Musée Pyrénéen within its walls — now the largest museum of Pyrenean arts and popular traditions.

The castle's chapel of Notre-Dame-du-Château houses furniture salvaged from the parish church of Saint-Pierre de Lourdes, demolished in 1904; the present chapel building was constructed with material reused from that church. Sited on a rocky promontory dominating the centre of Lourdes at the entrance to the seven valleys of the Lavedan, the castle is listed today as a monument historique and remains home to the Musée Pyrénéen.