The chapel is where St. Catherine Labouré reported the apparitions of 1830 that gave the medal its design, and it holds her body in a glass reliquary under the side altar and the relics of St. Louise de Marillac; St. Vincent de Paul's heart is kept in a reliquary above another altar. It is run by the Daughters of Charity, whose motherhouse surrounds it, and it sits through a courtyard off the street between the Bon Marché and the Sèvres-Babylone Metro on lines 10 and 12.
The weekly rhythm matters for planning. Tuesday is the Marian day, with celebrations at 12:30, 3:30, and 5:00 p.m. and the largest crowds; the rosary is prayed daily at about 3:30 p.m., the Stations of the Cross on Fridays at 3:30 p.m., and Vespers most evenings at 6:50 p.m. Pilgrims on the 27th of each month, the anniversary of the November 27, 1830 apparition, find the chapel full. Arrive fifteen minutes before any Mass if you want a seat.
Medals are sold in the shop beside the chapel, not inside it, and the sisters ask for silence in the chapel itself; a notice at the door reminds visitors it is a place of prayer and recollection. Hours shift on major feasts, in August, and when the chapel undergoes maintenance, so check the chapel's own schedule page the week you go. The existing pages on where the chapel is and on attending Mass there give the background; this page carries the current timetable as published on October 5, 2026.