Arreau has always been an important administrative and economic centre. The seat of the Quatre-Vallées judiciary until the 16th century, then a lieutenancy until 1789, Arreau was also a seat of archpriest. The economic crossroads of the Valleys of Aure and Louron, which even attracted Aragonese farmers, its fairs and markets, the drapery crafts from the 16th to the 17th centuries, the advent of thermal tourism in the 19th century and the arrival of the railway in 1897 gave Arreau this exceptional heritage, unique in the Hautes-Pyrénées. You will be able to discover many historical monuments such as the chapel Saint-Exupère, the house of the Lys, the castle of the Nestes, the school Saint-Exupère, the church Notre-Dame, the castle of Ségure, ...