Phase 2 of the Olympic sports complex in Oran was to build the 4000 seats swimming center and 6000 seat Omnisport arena. These two venues work with the natural topography, as does the main stadium, to facilitate crowd flow and flatter both structure and landscape. Formally these buildings explore a theme initiated by the stadiums tubular steel roof structure. Each building developpes a unique envelope to assure its identity and to create variety and interest across the 100he site.