The Vicario Viaduct is located in the A-44 motorway, in the South East part of Spain. It crosses a natural gorge by Rules Dam, near the town of Ízbor in the province of Granada. A single continuous steel-concrete composite deck, 24 m wide and 175 m long, divided in two 87.5 m spans, has been built. The cross section is a single structural steel box, 8.00 m wide and 4.52 m deep. The total width of 24 m is reached adding a strut and tie system each 4.375 m on both sides of the box, the steel parts of the deck were entirely constructed in the workshop and then they were erected on site just behind one of the abutments. Finally a 27.5 m long steel nose was connected to launch the deck. The main problems have been the curved shape of the deck (1420 m radius in plan) producing a non symmetric transverse distribution of reactions on each support and the cantilever reaching 87.5 m long, producing a maximum deflection of 1500 mm.