The city's subway system will become the seventh largest in the world once trains start running on 96 km of new tracks tomorrow, its operator said yesterday.

Three new lines - 6, 8 and 9 - and the extended sections of two existing lines - 1 and 4 - are scheduled to start operating at 9:30 am, taking the network's total length to 234 km, the longest in the country and seventh biggest in the world after New York, London, Tokyo, Seoul, Moscow and Madrid, Zhu Husheng, the general manager of Shanghai Shentong Metro Co Ltd, said.

"But we top all of them in terms of the speed of expansion," he said.

"None of them have ever added 96 km to a subway network in a single year."

Zhu said the extension will provide better passenger access to what is said to be one of the most crowded metro systems in the world. The existing five lines handle about 2.3 million rides every day, he said.

A passenger entering and leaving the network is counted as one ride.

During the National Day holiday in October, a record 2.81 million rides per day were recorded, with Line 1 being the busiest. The extension is expected to boost the daily number of rides by at least 700,000.

About 900 trains are currently running on the Shanghai metro, Zhu said.

"By 2012, the city will have about 2,500 subway trains, which will ease congestion significantly," he said.

Bi Xiangli, chief executive officer of the operator's research and consultancy company, said the metro was an important part of the city's urban development.

Before 2010, when the World Expo is held, the length of the metro will reach 400 km.

Under the existing plan, the system will be expanded to more than 800 km, Bi said. But no timeline has been set.

As well as the track extensions, 160 new stations will open tomorrow, including the east terminal of Line 8, which is located next to the venue for the 2010 Shanghai World Expo.

The new routes will also extend the subway to the suburb of Songjiang district, expanding the system's coverage to 13 of Shanghai's 19 districts.

Line 6, the only line operating solely in the Pudong district, will connect the major development areas of Waigaoqiao tax-free zone, Jinqiao export zone and Lujiazui financial zone.

Line 4, which crisscrosses five of the other seven lines for transfers, is aimed at making travel in the downtown area easier, officials said.

(China Daily December 28, 2007)