Famously home of the rose line in the Di Vinci Code but a wonderful church 
 
The Church of Saint-Sulpice in Paris is the second largest church in the city, located in the 6th arrondissement on the east side of Place Saint-Sulpice. It was built starting in 1646 on the site of a 13th-century Romanesque church, with construction continuing intermittently until the 18th century. The church is dedicated to Saint Sulpitius the Pious and is known for its Baroque architecture, featuring a grand facade designed by Giovanni Servandoni and two asymmetrical towers, one of which remains incomplete.
 
interesting facts:
In the novel Di Vinci Code the Rose line runs through the church  and holds the clue to the hoil grail (there is actually a line in there). Obviously this caused so much tourism that further filming was prevented, So Hollywood rebuilt the interior in a studio.