Intelier Palacio San Martín
In an unbeatable location across from Monasterio de las Descalzas Reales, this hotel—once the U.S. embassy and later a luxurious residential building crowded with noblemen—has the architectural bones of a turn-of-the-century mansion with its hand-carved ceilings, marble foyers, and intricate iron balconies. While the modern streamlined rooms are not exactly design-magazine material, they meet all your practical needs with good mattresses and plenty of storage space.