This church, the remains of a 7th-century collegiate church, is the oldest religious building in Lille and its surroundings. The Saint Piat sarcophagus in the Romanesque crypt dates back to the 3rd century. It's covered with a less antique slab of 'Tournai marble' (blue stone). The bell tower received a carillon in 1933. This carillon, consisting of 42 bells and weighing in at no less than 7 tonnes, is considered one the most tuneful in Europe. With 41 batons and 20 pedals, it has a very wide musical range. However, there's no bell ringer here - the carillon is operated by a huge spiked drum that automatically plays traditional French melodies ("Petit Quinquin", "Roi d'Agobert", "Mandoline d'Oiseau" and "Bon Tabac") every quarter-hour. It's a strenuous climb to the carillon, with 165 steps.