Beijing opened five new subway lines on Thursday, an urban planning show of force highlighting the investment the city has thrown behind public transport to curb its notorious air pollution and traffic congestion. Costing nearly 61 billion yuan ($9.2 billion), the newly constructed lines — most connecting the distant and dusty suburbs to the city centre — bring Beijing’s subway network to 336 km (209 miles). That distance is just a fraction of what the city government has planned, the Beijing Municipal Commission of Transport told reporters at the unveiling of the city’s No. 15 line.

Beijing aims to have a 561-km-long subway network by 2015, and is planning for between 700 and 1,000 km by 2020, Li Xiaosong, the deputy director of the commission said.

“If we are comparing ourselves to London, New York or Tokyo, we are still in the early stages of development, but this shows the Beijing government’s strategic investment priority in public transport,” Li said.

At rush hour on some of Beijing’s central subway lines, queues with Beijing’s 5.3 million daily riders can be three and four trains deep, with platform attendants pressing arms and legs in behind closing train doors.The city has invested more than 250 billion yuan in rail and road links over the past five years, 51 percent of which went to public transport, Li said.

With the flurry of subway construction, city leaders are attempting to make good on promises to clean up Beijing’s skies and clear traffic gridlock. In January, Beijing Mayor Guo Jinlong promised to give greater priority to public transport by building bus lanes and new subway lines and removing high-emission vehicles from the road.