The history of Paris can be read by following the banks of the Seine. The first occupants of the region (the Parisii) founded a Gallic city on the present site of Nanterre. In the 1st century AD, the Romans mentioned a “Lutetia Parisiorum” located astride the Ile de la Cité and on the left bank of the river. From the Middle Ages to the 20th century, architectural treasures were built along the Seine. The Gothic of Notre-Dame and the Sainte-Chapelle rubbed shoulders later on with Haussmannian architecture. At the heart of France’s economic and administrative power, the banks of the Seine have been listed as a Unesco World Heritage Site, since 1991.