NBC - China's rulers are planning a megacity that would be home to 130 million people and cover an area the size of New England.
Sitting on the northeast coast of China, Jing-Jin-Ji — which stands for "Beijing-Tianjin-Hebei" — is a central plank of the country's economic development plan over the next century.
The sheer numbers are startling. In November, the government approved $36 billion to build 700 miles of rail within three years.
Residents of bedroom communities just outside Beijing's city limits, who now spend five to six hours a day on their commutes, are expected to be the main beneficiaries of a new transportation system serving the megalopolis.
With 13,670 miles, China already boasts of the world's longest network of high-speed rail lines, which serve trains traveling 120 mph to 220 mph. The next two countries are Spain, with 1,930 miles, and Japan, with 1,887 miles. And China plans to build 10,000 more miles.