Beijing opened its first new underground line in 40 years yesterday, in a further sign of its resolve to ensure the success of next year's Olympics.

Members of the public rode on the Beijing No 5 Line, which is every bit as smart and swift as the latest systems to open in Hong Kong or London. The marble station floors, the electronic travel guides and the gleaming steel sliding doors are a far cry from the city’s other two lines, which were built in the late 1960s and look as if they have barely changed since.

The new line, which is one of several being built for the Games, cost 12 billion yuan (£800 million) and took five years to build. It is the first in Beijing to run north-south. It is also the first to be completed since Lines 1 and 2 were tunnelled out by the army as part of a defence system to protect the city in case of attack, after China’s relations with the former Soviet Union soured in the early 1960s.

The 27.5km (16½-mile) line will be followed by the opening of three more lines next year that will expand the city’s mass transit system to about 200km, in an attempt to relieve pressure on the transport system prior to the Olympics.

A light railway will also be opened next June to link the city with a huge new airport terminal — bigger than Heathrow Terminal 5. By 2015 Beijing aims to have 561km of subway — exceeding the 408km run by London Underground. Beijing residents turned out in force to glimpse Line No 5, the first Olympic-linked structure in a project costing at least $37 billion (£18 billion) to open to the public. Most were thrilled by the clean, high-technology line on which trains can run at up to 80km/h (50mph).

White-gloved security guards directed commuters down the escalators and past signs reading “No 5 Line, a line to a better life”. Crowds of sightseers, many armed with video cameras to record the historic moment, packed the trains to bursting point.

Dozens of female subway workers tried to guide travellers into queues to get into the crowded trains. One said: “It’s not usually like this, especially on a Sunday.”

In a move that will make busy London commuters envious, the line is shallower so that mobile phones will never lose their signal. And the carriages will also be equipped with televisions that can broadcast live programming — a boon for sports fans en route to the Olympics.

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