Who hasn't dreamed of seeing the inner workings of a top museum? That's what a small group of Time Out editors were able to do when we were guided around the warehouse where they store, restore and register many of the foundation's works of art. In the building's basement, with a constant temperature of 21 degrees Celsius and humidity kept between 50 and 51 percent, there are around a thousand works of contemporary art by artists who fill art history books such as Tàpies, Basquiat, Richter – the most sought-after living artist in the world – Baselitz, Sert, Barceló, Julian Schnabel... They've also got a space dedicated to black-and-white photography, and another, more delicate, for colour, where works by the likes of Robin Rhode, Andreas Gursky, Thomas Ruff, Gabriel Orozco are stored. And the graphic art section features more than 4,600 lithographs, prints and engravings. Among the names here are some impressive biggies as well: Christo, Joan Brossa, Joan Miró, Eduardo Chillida, Francis Bacon... And that's just part of the collection. The other part, with the large-format installations, is kept in a different warehouse, and we're not going to tell you where it is, because they didn't tell us! Because clearly we don't know how to keep a secret.