Torres Blancas

Sáenz de Oíza's organic 1960s concrete tower in Prosperidad — a Brutalist-meets-futurist landmark of curving balconies and tubular cores that, despite its name ('White Towers'), is a single rugged structure of raw concrete. Conceived as a vertical garden city, it's one of the most celebrated works of 20th-century Spanish architecture, beloved by enthusiasts for its sculptural, almost biological forms. It remains a private residential building. For architecture travelers, the exterior is the reward — an audacious, organic high-rise unlike anything else in Madrid, and a key monument of postwar Spanish modernism well worth the trip out from the center.