Musée Carnavalet

The fascinating 140-room museum, located in a 16th-century mansion, shouldn’t be missed. Converted to a museum in 1866 by Baron Haussmann, the man responsible for rebuilding much of central Paris in the 19th century, the museum is focused on the history of Paris in the broadest sense—its collections include everything from wooden punts used by the Parisii, the tribe that inhabited the islands in the Seine before the Romans arrived, to a re-creation of Marcel Proust’s decidedly odd cork-lined bedroom (he insisted on silence when he worked). Closed Monday.