Delhi’s Dr S. P. Mukherjee Swimming Pool Complex features an Olympic-size swimming pool for the Commonwealth Games in 2010. The roof structure has elliptical shape in plan with main dimensions of 150 m x 129 m. Based on a rectangular grid two layers of parallel strand bundles span in between the massive compression ring. Both layers are spread apart by flying masts, forming a three dimensional lens shaped structure. For this application the strand technology normally used for pre-stressed concrete bridges, was further developed. The fully insulated roof cladding consists of aluminum metal deck with a metal roof cladding. The concrete compression ring is supported by 32 radial arranged concrete shear walls. The glass façade with horizontal sun louvers creates the generous interior space needed for a state of the art swimming complex.