Versailles

It's hard to tell which is larger at Château de Versailles—the world-famous château that housed Louis XIV and 20,000 of his courtiers, or the mass of tour buses and visitors standing in front of it. The grandest palace in France remains one of the marvels of the world. But this edifice was not just home to the Sun King, it was also the new headquarters of the French government (from 1682 to 1789 and again from 1871 to 1879). To accompany the palace, a new city—in fact, a new capital—had to be built from scratch. Tough-thinking town planners took no prisoners, dreaming up vast mansions and avenues broader than the Champs-Élysées.