To mark the 300th anniversary of its foundation, Caja Madrid commissioned the architect and sculptor Santiago Calatrava to design a monument that would be donated to the Villa de Madrid. It was conceived as a monument able to describe a helicoidal movement, yet the hefty maintenance costs led to the Ayuntamiento de Madrid's preference for keeping it "static". According to the initial project, the work would measure 120 meters tall. However, the complex network of tunnels that pass underneath the Plaza de Castilla made this original project unworkable, because of its weight. A decision was therefore made to lower the height to 92 metres. In early October 2007, the Caja contracted construction company Acciona to carry out the project, and in July of the following year building work began, having dismantled the fountain which existed previously at the selected spot.The obelisk was unveiled on 23 December 2009 by Juan Carlos I.
Description
Caja Madrid decided to call the Obelisk construction of the Fund, although given the way pyramid of such a monument, not an obelisk itself. In fact, its design is inspired by the Column of Infinity, a work of 29.33 meters in height by Romanian sculptor Constantin Brâncuși, built in 1938 in Târgu Jiu. Calatrava described his work as "a mobile obelisk participating in the masculinity of the vertical and the delicacy and femininity of movement." The inner core of the work, 92 meters high, is a cylindrical metal shaft of equal length and 2 meters in diameter, which rests on three metal legs. These, which weigh 50 tons each, are based in turn on three concrete piles 80 inches in diameter and 26 meters long. Instead of supporting the mast directly above its long axis, it was decided to do it this way to not make extreme demands on pre-existing tunnel at the site. By fixing shaft through joints, 462 ribs and 462 bronze strips 7.70 meters in length, lining the entire obelisk. These strips have a tilting movement transmitted through the ribs, giving the appearance of an outwardly moving wave of ascension along the spine.