Impressed by the development of high-speed rail, a retired Hong Kong businessman spent two and a half years and more than 77,000 U.S. dollars building a model of the control system of high-speed railway.

China's total railway mileage reached 146,300 km by the end of last year, with 37,900 km of high-speed rail, data from China State Railway Group Co., Ltd. showed.

Produced by Xinhua Global Service