Eglise du Val-de-Grâce

Anne of Austria, the wife of Louis XIII, vowed to erect 'a magnificent temple' if God blessed her with a son. She got two. The resulting church and surrounding Benedictine monastery - these days a military hospital and the Musée du Service de Santé des Armées - were built by François Mansart and Jacques Lemercier. This is the most luxuriously baroque of the city's 17th-century domed churches, its ornate altar decorated with twisted barley-sugar columns. The swirling colours of the dome frescoes painted by Pierre Mignard in 1669 (which Molière himself once eulogised) are designed to give a foretaste of heaven. In contrast, the surrounding monastery offers the perfect example of François Mansart's classical restraint. Phone in advance if you're after a guided visit.