Palacio de Cibeles, Madrid

The Palacio de Cibeles (Cibeles Palace) is one of the most impressive buildings in Madrid. Originally built as a post office and telecommunications centre, it was known as the Palacio de Comunicaciones (Communications Palace). It was the largest post office building in the world. At 12,000 square meters and 70 meters high, it easily beat the 4,000 square meters of the Chicago office.