China is in the midst of several megaprojects that will transform its cities.

Over the next decade, China plans to encourage 250 million people (29 times New York City's population) to move into the country's growing megacities. To cope with that huge migration, the country has invested tens of billions of dollars in giant infrastructure projects.

This summer, China will open its most ambitious megaproject yet, a bridge that connects Hong Kong, Macau, and the mainland's southern city of Zhuhai. Stretching 34 miles, it's the world's longest cross-sea bridge, according to the AFP. Take a look: