Tongliao, China

2.8 million people crammed into a sprawling 23,000 square mile prefecture - that's the reality of living in Tongliao, China. The city proper has under a million residents, but the broader metro area is a vast, sparsely populated expanse of plains and foothills. Bureaucracy is a persistent headache, as Tongliao has bounced between provincial administrations for decades. And with a frigid, dry continental climate, the weather can be a challenge. This is a frontier city best suited for those seeking a rugged, remote experience in China's northern hinterlands.