The two edifices which now make up the Musée national du Moyen Age - Thermes et hotel de Cluny have a history of their own. The Gallo-Roman baths are vestiges of a time when Paris was called Lutetia. How did the thermae operate? Where did the bathers go? The Cluny abbots' former mansion, an important medieval monument, became a 'national property' during the French Revolution. The building was made into a museum in 1843 and restored in the second half of the nineteenth century. This book, enriched with plans and illustrations, takes an historical and architectural approach to Cluny, inviting visitors to discover an astonishing fragment of a bygone world tucked away in the very heart of Paris.