The 1929 Hotel Castelar was a stopping point for Spanish literary stars during the golden years of the 1930s. Federico García Lorca lived here in 1934, and his room is preserved as a museum. The lobby retains many original brass, marble, and heavy plaster elements, including in the dining area, which was once a confitería (cafe) as important as Café Tortoni. Mario Palanti, eccentric architect of nearby Palacio Barolo, designed the Castelar. The spa in the basement is free for guests (men and women are separated), with fees for various services. Even if you're not staying here, it's worthgetting a treatment  to see the Turkish-style, white Carrara marble space. Rooms are contemporary but with 1920s wooden touches, speckled glass, and tiled bathroom floors (original to the building). Guestrooms are not large, but have a small antechamber adding a sense of privacy. Suites have an added living area.