The Denmark Pavilion encourages visitors to ride bicycles through its spiraling white venue with the beloved Little Mermaid statue at the heart.

China, once reputed as a country of bikes, has 192 million motor vehicles. Beijing alone has 4.13 million. Congestion is almost an all-time occurrence in the gridlocked capital.

Shanghai is more sober-minded in its restriction of the car fleet. The city imposed quotas on car ownership in 1986, according to which license plates are issued on a quota basis and are auctioned for an average of 40,000 yuan (5,300 U.S. dollars), half the price of a Volkswagen Jetta sedan.

Still, congestion is a bottleneck for the city with 18 million people and an estimated 1.6 million motor vehicles.

In response to the expanding fleet, deteriorating air quality and subsequent climate changes felt by many, cities have moved to promote the low-carbon drive, telling everyone to take the public transport, spare air conditioners as much as possible and buy low-emission furniture and home appliances.

Automakers have conjured up new, low-emission cars, some of which are on display at the Expo.

The Expo lasts only six months. But the low-carbon message it sends to the human race, however, will hopefully stay.

As far as the urban traffic is concerned, sometimes bikes and hikes can solve some of our problems.