Fast forward to the year 1605, when King Henri the Fourth decided to transform Le Marais into the ultimate aristocratic address. He commissioned the construction of the Place Royale, known today as the Place des Vosges. This is the oldest planned public square in Paris, and its design was revolutionary. Look for the distinctive architecture: 36 identical pavilions built of red brick, white stone, and blue slate roofs, all connected by elegant vaulted arcades. It was designed to host royal events, tournaments, and parades, most notably the wedding celebrations of Louis the Thirteenth and Anne of Austria in 1612. This royal endorsement triggered a building boom. Wealthy nobles rushed to build their own Hotels Particuliers, or grand private mansions, throughout the neighborhood. One of the best surviving examples is the Hotel de Sully, just a short walk from the square. These mansions were designed with a "cour d honneur" or front courtyard and a private garden in the back, creating the high-walled, secretive atmosphere that still defines the quiet side streets of the Marais.