Bangkok's long-awaited underground commuter railway will open in April 2004, four months ahead of the last revised schedule. The launch was initially planned for July 2003, but later postponed to August 2004. Siemens AG, the train supplier for the project, will deliver 11 out of the total 19 trains in September, reported The Associated Press. Construction of all the 18 subway stations has been virtually completed, and test runs will start late this year, said the AP. Home to more than 4 million cars, trucks, buses, vans and motorcycles, Bankok has some of the worst traffic jams in Southeast Asia. The opening of the subway system is expected to ease the city's traffic congestion, where hour-long traffic delays are common.