for the football final. The turf system consists of natural grass in modular containers which incorporate irrigation and drainage systems. Design Construction The foundation stone for the Olympic Stadium was laid on 7 January 1980. Its construction was revolutionary and involved the use of a prefabrication method for the 34 sets of pillars supporting the stands (each weighed 600 tons). About 26,000 seats of the lower tier were covered, while the stadium's most striking feature were the four leaning pillars that held its floodlights, each being 62 metres tall. The Athens Olympic Stadium was finally inaugurated in September 1982. Renovation The stadium was renovated from 2002 until 2004 adding the famous roof for the 2004 Summer Olympics. The central lawn of O.A.K.A consists of approximately 6.000 plastic capsules inside which thermophile lawn is grown. The capsules are adjoining, their size is 1.2*1.2m and are situated on a flat cement surface of two acres, flanked by two lateral drainage channels. The irrigation of the lawn is achieved by 35 automatically elevated water launchers with the use of programmed irrigation. This system allows the movement of the lawn to an area outside the stadium in order for the surface to be used for different events. Thirty-four entrance gates provide access to the stands. Odd gate numbers (1 to 35) lead to the lower and even numbers (2 to 34) to the upper tier. There are no gates numbered 18 and 36, since the two video-scoreboards are located in their place. Additionally, the stadium features 17 VIP boxes and 3 parking lots. Due to its design, the stadium's tribunes have the ability to empty within 7 minutes. Competition Area Roof Designed by the world-known Spanish architect Santiago Calatrava, the roof cost €130 million. The two giant arcs have a total span of 304m and a maximum height of 72m. The roof has a total weight of 18,700 tons coverering by 5,000 polycarbonate panels which covers an area of 25,000 square metres. The west arc was assembled 72m from its final position and the east 65m - both later slid into place. The roof is designed to withstand winds up to 120 km/h and earthquakes up to magnitude 8. Transport Access by: Car - Exit the city centre to the north via Kifissias Avenue and just follow the road signs to "OAKA". If you come from the Attiki Odos ring road, use exit 11