Dax Cathedral is a Roman Catholic church in the town of Dax in the Landes département of France.
The diocese of Dax was not restored after the French Revolution but with several others, including Aire, was added to the Diocese of Bayonne by the Concordat of 1801. In 1817 the former dioceses of Dax and of Aire were again separated from that of Bayonne and joined to form the new Diocese of Aire and Dax, of which the bishop's seat was at Aire Cathedral.
In 1833 the bishop's seat was officially transferred to Dax and to Dax Cathedral. Aire Cathedral remains as a co-cathedral.
Wikipedia https://en.wikipedia.org/wiki/Dax_Cathedral
Coordinates 43°42'30.459" N -1°3'10.741" E