The Banco de España palace was commissioned by King Alfonso XII at the end of the 19th century and was then expanded on three occasions, the last being a few years ago. Inside there are numerous works of art, including portraits of kings and nobility painted by Goya, and the famous "Camara del Oro" which houses about one hundred tons of gold! It is located fifty meters underground and is protected by armored doors and a moat which will fill up with water if necessary. What's more, one of its rear towers has a hidden helipad, which is apparently never used!