Beijing To Build Biggest Metro System In The World

"Fifteen of the new lines will support urban areas, while the remaining four will stretch out to the suburbs, according to the plan drafted by the city's communications commission.

Currently four metro lines serve Beijing. Lines 1 and 2 span 54 kilometres, while Line 13 and Baton Line cover 61 kilometres. Together they carry 1.5 million travellers every day.

The three lines Line 4, 5 and 10 that are currently under construction are expected to be operational for the 2008 Olympic Games.

Beyond building new subway lines, transportation experts have been exploring other possibilities for the city's underground space to help ease the traffic pressure.

During a conference this weekend entitled the "International Academic Conference on Underground Space," the Beijing Urban Planning Commission and Beijing Urban Planning and Designing Research Institute jointly released a new plan proposing the construction of six underground expressways by 2020 to further ease traffic congestion, mainly within the second and third rings."