The main building on the Plaza de la Puerta del Sol houses the regional government of the Comunidad de Madrid. The Casa de Correos was built as the city’s main post office in 1768. The clock was added in 1856 and on New Year’s Eve people throng the square to wait for the clock to strike midnight, and at each gong swallow a grape – not as easy as it sounds! The building was undergoing major restoration works when we visited.

　　On the footpath outside the Casa de Correos is a plaque marking Spain’s Kilometre Zero, the point from which Spain’s network of roads is measured.