Madrid's town hall and one of the most visually arresting buildings in the city — a vast white wedding cake of carved limestone, finished in 1919 to a design by Antonio Palacios in a half-imagined "Spanish plateresque" style. It originally housed the central post office, until it was converted to municipal use in 2007 and renamed CentroCentro.
The interior is open to the public free of charge — an enormous skylit hall with cast-iron staircases and the original post-office counter intact — and houses exhibition spaces and a café. The big draw is the viewing platform on the eighth floor (small entry fee), with a 360-degree terrace looking down both halves of the Paseo del Prado-Recoletos axis. There is also a respected restaurant, Palacio de Cibeles Terraza, with a rooftop view across to the Bank of Spain.