CaixaForum Madrid is a museum and cultural center in Paseo del Prado 36, Madrid. It is sponsored by La Caixa. It was constructed by the Swiss architects Herzog & de Meuron from 2001 to 2007, which combined an old abandoned electrical station with new construction of floors encased with oxidized cast-iron, which was meant to be of a similar color and weight as the brick below. On the house next to it, there is a green wall designed by French botanist Patrick Blanc.