Midstream in the Seine, the Île de la Cité is Paris's birthplace, where a Celtic tribe known as the Parisii built their wattle settlement around 250 BC. The island is bound to the mainland by four bridges, including the city's oldest”the now mislabeled Pont Neuf ("new bridge"). To get a sense of what the island was like before Baron Haussmann totally redeveloped it, visit the archeological crypt (1 Place du Parvis de Notre-Dame; 33-1-55-42-50-10), the pretty Place Dauphine (Between Pont Neuf and Rue de Harlay), and the side streets on the north side of Notre-Dame. Sainte-Chapelle, a masterpiece of Gothic architecture, is always mobbed for its stained glass; to beat the crowds, try going to an evening concert, especially in summer, when the days are long and the light through the stained glass is gorgeous until 10 p.m. (4 Blvd. du Palais). On the upstream tip of the island, behind Notre-Dame, the Deportation Memorial is a moving monument to French citizens who were deported and died in Nazi camps.