The Grand Mosque is the largest and oldest mosque in the world and surrounds one of the world's holiest places, the Kaaba. The "King Abdullah Haram Expansion" Project is the largest expansion of the Grand Mosque in its four thousand year history. The new expansion will comprise new pray-yards, walkways, tunnels and the development of existing service facilities to increase capacity of the mosque to more than 2 million people. The project consists of 18 Zones covering (Haram, Piazza & Bridges) with total up area 750,000 SQM.