This street, laid out above a warren of tunnels belonging to the Saint-Germain abbey, is lined by a succession of beautiful mansions: Hôtel Biron, home to the Rodin Museum, Hôtel de Broglie (N° 73), de Villeroy (N° 78), de Castries (N° 72), de Gouffier de Thoix (N° 56), and de Boisgelin (N° 47). The most famous is without doubt Hôtel Matignon, built in 1722 and the former property the Austro-Hungarian ambassador Talleyrand. Since 1958, it is the official residence of the French Prime Minister.