The Maison Louis XIV, also known as the Maison Lohobiague, is a 17th-century Basque mansion on Place Louis XIV where the Sun King lodged in 1660 before his marriage. The building is one of the best examples of Basque merchant architecture of the period: solid, stone-faced, with dark carved wood shutters and a courtyard behind heavy gates.
The interior has been restored to roughly its 17th-century appearance and is open for guided tours in summer. The rooms contain period furniture and documents relating to the royal stay and the Treaty of the Pyrenees. The tour is conducted in French but is short enough (about 45 minutes) to follow even with limited language. It is worth doing if you have an interest in the political context behind the wedding, which was as much a diplomatic arrangement as a personal one.