Bangkok’s new subway opened for a six-day trial April 12 to show residents what to expect when the mass transit system officially opens in June after long delays. The first section to go into operation will be a 12-mile stretch from the northern suburbs to Chinatown. The full network is scheduled for completion by the end of the decade and will encompass 69 miles or track. Bangkok has some of the worst gridlock in the world and a skytrain that opened in 1998 to much fanfare proved to be a failure because it didn’t reach the suburbs and was too expensive for the average Thai. Bangkok’s traffic problems eased during the economic crisis in the late 1990s but have returned with a strengthening economy.