Infrastructure development has become a means to shorten the gap between China's major and smaller cities. China began building its first high-speed passenger rail network in 2007 and has continued to expand it rapidly. Over 25,000 kilometers are in service as of this year, making China's high-speed network the world's largest.

25,000 kilometers -- that's three-fifths of the nation's total railway mileage, and two-thirds of the world's high-speed railway mileage. According to a plan released in 2016, the country's high-speed rail network will reach 38,000 kilometers by 2025, connecting all provincial capitals and cities with a population of over 500,000.

China's capital Beijing has always been at the receiving end of development in northern China. Its neighbor Tianjin, another municipality, is relatively less developed. But bullet train service that began there in 2008 has changed the situation. The Beijing-Tianjin High-Speed Railway quickly expanded internal consumer demand in the two cities: Beijing's first-half GDP in 2009 reached 10.1%, while Tianjin's reached 16.6%.

The high-speed railway network is significantly impacting labor productivity, jobs, industrial growth and regional development. Take the Beijing-Shanghai High-Speed Railway, for example. The initial construction investment was about 60 billion yuan. The large-scale investment created demand for more than 2 million tons of steel products, 12 million tons of cement, and another 600 thousand jobs in the cities along the railway.

What's known as the "Four Vertical and Four Horizontal" high-speed railway network has mostly completed by late last year. According to the National Development and Reform Commision, an "Eight Vertical and Eight Horizontal" network will almost double the route length. By 2020, the total length of China's total high-speed railways will reach 30,000 kilometers.