Artery that provides an economic lifeline

"The G2 has become an indispensable friend to me since I bought an apartment in Langfang in 2013, ending my renting life in Beijing," he said. "The expressway has helped me keep my job in Beijing while buying an apartment with my wife and children."

Like Zuo, many young people who cannot afford an apartment in Beijing have chosen Langfang, on the capital's outskirts, to settle down. The G2 has made it a reality for them to lead a two-city life.

China now has the world's largest expressway network, stretching 160,000 kilometers, long enough to circle the Earth four times. Those expressways have made people happier and wealthier and promoted regional economic growth along the roads.

The G2, 1,218 km long, links Beijing and the country's economic center, Shanghai, running through Tianjin municipality and Hebei, Shandong and Jiangsu provinces. It is a critical artery of the integrated economic development of the Beijing-Tianjin-Hebei region and the Yangtze River Delta region.

Construction began in December 1987, and the first section, linking Beijing and Tianjin, was opened in 1991.

At the very beginning there were just 153 km of expressways in six municipalities and provinces along the road. Now, it has formed an expressway network of more than 20,000 km in total in these areas. The overall economic output of those six municipalities and provinces, a mere 3 trillion yuan ($459 billion) in 2000, was 10 times that sum at the end of last year, according to government figures.

At 2 am in the Wuqing district of Tianjin, Zhu Fujie, a manager of an agricultural company, takes stock of produce as it is loaded into two trucks.

Those items, worth 90,000 yuan, will be transported to Beijing for sale. Using the G2, the trucks will arrive in Beijing about three hours later. Their freshness means better returns for farmers, a report by Economic Daily said.

"G2 is a road toward wealth for us," Zhu said. "We used to sell our vegetables in nearby markets only, so we couldn't make that much money. The G2 helps us to get our products to Beijing, a much better market."

Because of the convenient transport from Beijing to Tianjin, collaboration between the two cities is growing. In the past seven years, more than 1,000 projects from Beijing have been set up in Wuqing, with total investment of more than 50 billion yuan.

"Wuqing has been working on building platforms on research, manufacturing, marketing and financing sectors for the commercialization of scientific findings in Beijing," said Zhang Weiqi, head of the science and technology bureau of Wuqing district.

The G2 has become an important framework of Beijing-Tianjin-Hebei integrated development.

Along the expressway are 11 modern zones such as economic and science technology zones and bonded zones. The G2 and two other expressways, Beijing-Tianjin and Beijing-Taipei, have helped make transport between Beijing and Tianjin port, the biggest comprehensive port in North China, much more efficient.

Up to 70 percent of the cargo arriving at the port is from Beijing, Hebei and Tianjin, which has boosted regional economic growth.

Fast economic growth has in turn generated demand for bigger and better expressways. In the past 20 years many sections of the G2 have been expanded to six or eight lanes.