Architecture of Madrid of Music is a work of 1988. In the 21st century, Madrid faces new challenges in its architecture. An old industrial warehouse is the Interpretation Centre of New Technologies, and the CaixaForum Madrid (Herzog & de Meuron) was a former power station. Under the government of Alberto Ruiz-Gallardón the four tallest skyscrapers in Spain were built, and together form the Cuatro Torres Business Area (CTBA). The Manzanares River is crossed by new edge bridges, and work started on the International Convention Centre (Mansilla+Tuñón), an original round building, whose works remain paralyzed by the crisis. Caja Mágica (Dominique Perrault) sport centre
Allison Engine Testing Stands by servicemen of the 44th Depot Repair Squadron of the USAAF 81st Air Depot Group; two enclosed engine stands constructed by the Allied Works Council; two open stands of unknown construction; and a concrete pavement area which is the site of former associated buildings. The first Allison Testing Stands were constructed on the eastern side of Schneider Road and the Eagle Farm Aerodrome in November–December 1942 as a consequence of arrangements made for Australia to serve as a stronghold for United States (US) operations in the Pacific during World War II (WWII). The area, however, had previous links with aviation.