The City of Riyadh, Saudi Arabia, is building the world's largest public transit system --- in just five years. It will be presenting the project at the Palais des Congrès, in Montreal, Quebec, during the global summit of the Union Internationale des Transports Publics (UITP), this week. Managed by The High Commission for the Development of Arriyadh (HCDA), the project includes six metro lines covering 176 km and 85 stations, in addition to 24 bus routes covering 1,900 km and 3,000 stations and stops. At a