For those of you who have ever wondered what it's like inside, the Palacio de Cibeles (that's the very ornate white building by the Cibeles fountain), it will opening its doors to the public until 27th July. Visitors will have access to 8 floors of cultural space, totalling some 45,000 square metres, as well being able to climb up to the roof terrace to enjoy panoramic views of the city. The building, previously used for telecommunications, has just undergone major refurbishment lasting six years and costing 125 million euros, and in September a cafeteria and restaurant will open on the upper floors.
The building is open from Tuesday to Sunday 10am-8pm until 27th July. Entry is free. It's located on the Cibeles roundabout where Paseo del Prado and Calle Alcalá meet (metro: Banco de España L2).