The Aître Saint-Maclou is a small, square enclosure behind the church of the same name, surrounded by half-timbered galleries dating from 1526. Originally an ossuary for victims of the Black Death, it is one of the very few surviving medieval plague cemeteries in Europe — and unique in the macabre carved decoration of skulls and bones on the timber posts and beams.
A long, slow restoration finished in 2020 and the courtyard is once again open to the public. There is a small bookshop and exhibition space inside; the cobbled square itself, with its mummified cat in a wall-case, is the main attraction.