The Sapieha family made its mark with numerous foundations in the history of the resort of Biarritz. However, few traces of them remain. The Sapiehas funded a stretch of highway near the town in the 19th century, and they also carried out charitable activities. There is still a small rue Sapieha, as well as a large park (now Parc Impérial) opposite the Saint-Charles church next to a former residence belonging to the family (the neo-Renaissance Villa Sapieha, between avenue de la Marne and rue Tastoua, probably built before 1879 to a design by Eugène Monnier). At the end of the 19th century, it housed, among other things, an excellent collection of paintings by Count Michał Pac through family connections.

The mausoleum of several generations of the Sapieha family, meanwhile, was built in another part of the city, in one of the side cemeteries, next to the small church of Saint-Martin. The neo-Gothic, magnificent, multi-storey monument stands in the middle of a plot fenced off with an ornamental iron fence (in stylised interlocking ogival arches), on a two-storey stone platform. The pointed-arched niches contain marble plaques with engraved details of the buried (front, back and left walls), the Sapieha family coat of arms Lis (right). Buried in the family tomb are Duke Franciszek Xawery, son of Duke Pavel, who died in Biarritz in 1882, the first representative of the family to reside there; his wife Ludwika of Pacs (d. 1895); their son Franciszek Xawery (d. 1889); Duke Lew Kazimierz (d. 1904) and Countess Maria of Sapieha Potocka (d. 1923); Duke Ludwik (d. 1937) and Elżbieta Sapieha (d. 1935). To emphasise the magnificence of the great family, Latin inscriptions were used and the names of the persons are also given in this version.

The cemetery is neglected and the mausoleum itself is badly damaged: several pinnacles are lying on the ground, most of the sandstone parts show signs of dampening and their surface is weathered (e.g. the owls crowning the first storey, which are no longer legible). Near the Sapiehs' tomb are several more impressive mausoleums, including the badly deteriorated mausoleum of the English Osborne family. The dilapidated, forgotten and hitherto historically unexplored monument to one of the largest Polish magnate families in the famous resort is one of the most mysterious Polish monuments on French soil. The tomb of another branch of the Sapieh family rises in the Montmartre cemetery in Paris.