A Shanghai advertising¹ firm is offering people throughout the country up to 1 million free bicycle rides a day, as part of a marketing² ploy³ that will run until 2010.

After registering their ID cards, cyclists can pick up and drop off their Ibike Media bikes at any of the firm's service stations.

People can rent the bikes for up to four hours at a time, said Li Yi, a company spokesman.

The company has 110,000 bicycles, which are available to borrow in Beijing, Shanghai, Tianjin, Hangzhou, Jinan, Changzhou and Changsha, he said.

Each bicycle could be used by 10 people a day, which makes up the 1 million rides, Li said.

Most of the service stations are located in local communities, and near metro⁴ stations and universities, he said.

"As rising petrol prices are making more people opt⁵ for two rather than four wheels, the service is pretty popular," Li said.

In Shanghai, cyclists will have access to 1,500 service stations and between 60,000 and 80,000 bikes, he said.

Jin Li, an engineer who lives and works in Shanghai, said: "Not many buses go to my workplace, and the roads are always jammed at rush hour, so riding a bicycle is the best option."

The free service can also help reduce bicycle theft and eliminate maintenance expenses, Li said.

"Each bicycle is equipped with a GPS satellite signal transmitter," he said.

"If stolen or damaged, the bicycle automatically locks and the positioning signal pinpoints⁶ exactly where it is," he said.