The origins of this church stretch back over a millennium. First established by King Childebert in 543 who constructed a basilica and monastery on the site, it was built, destroyed, and rebuilt several times over the centuries. Nothing remains of the original buildings, but the bell tower dates from the 10th century and is one of the oldest in France. Most of the rest of the church was built in the 11th and 12th centuries and is Romanesque in style. The church and its abbey became a major center of learning and power during the Middle Ages, remaining a force to be reckoned with up until the eve of the French Revolution. Once the monarchy toppled, however, all hell broke loose: The abbey was destroyed, the famous library burned, and the church vandalized. Restored in the 19th century, the buildings have regained some of their former glory, though the complex is a fraction of its original size.

The first thing you’ll notice on entering is that much of the interior is painted in a dazzling range of greens and golds—one of the few Parisian churches to retain a sense of its original decor. Several murals by 19th-century artist Hippolyte Flandrin fill the archways in the nave. The heart of King Jean Casimir of Poland is buried here, as are the ashes of the body of René Descartes (his skull is in the collections of the Musée de l’Homme). On the left as you exit you can peek inside the chapel of St-Symphorien, where during the Revolution over 100 clergymen were imprisoned before being executed on the square in front of the church. The chapel was restored in the 1970s and decorated by contemporary artist Pierre Buraglio in 1992.

Classical music concerts are regularly held in the church on Thursday and Friday evenings. (Tickets and information are at On the last Sunday of the month, afternoon organ recitals are free.