Originally scheduled for completion in 2009,[5] work was significantly hampered by the economic crisis of 2008 which seriously affected the real estate sector in Spain.

[9] The building consists of two parallel towers separated by a gap of 20 metres (66 ft) and connected by a cone-shaped structure between floors 38 and 44.

Its frontal view, vaguely resembling the number 11 and the letter M, has led commentators to speculate about a possible reference to the terrorist attacks of 11 March 2004 in Madrid.

[6] While reports that the building did not include elevator shafts[6] were false,[10] poor planning led to unsafe working conditions for the builders, construction outpacing design, and a construction elevator collapse which injured several of the thirteen workers aboard.

Efforts to assist these people were hampered by design flaws which did not permit emergency vehicles onto the building site.