The Atocha station memorial is a memorial monument located at Atocha station in Madrid, Spain, that commemorates the 191 victims of the 11 March 2004 Madrid train bombings and the special forces agent who died when seven suicide bombers blew themselves up on 3 April 2004.
The 11 m tall (36 ft) cylinder stands above Atocha station, the destination of the four trains that were attacked. Thousands of messages of condolence made in the days after the attacks are inscribed on the inside of the tower. The messages of grief can be seen from a chamber beneath the hollow monument.
King Juan Carlos, Queen Sofia and Prime Minister José Luis Rodríguez Zapatero attended a ceremony at the site. Wreaths were laid at the foot of the tower and mourners observed three minutes of silence.
Texts composed of hundreds of expressions of grief sent in the days after the attack from all over the world are printed on a clear colourless membrane that is inflated by air pressure, rising balloon-like inside a cylinder. That structure is composed of glass blocks and sits on a platform or terrace overhead. The light in the empty blue room below comes from this source alone. At night the cylinder is illuminated by lamps within its base and can be seen throughout the station neighborhood.