Considered by many to be the world's narrowest city, Yanjin hugs the Nanxi River as it runs through the steep mountains of northwest China.

When viewed from above — a winding river sandwiched between a slim row of tall, narrow buildings — this city in the Yunnan province doesn't seem real. The widest sections of the city measure less than 1,000 feet across, and at its narrowest point, Yanjin is less than 100 feet wide. There is one main road on each side, running parallel to the river, and fewer bridges than you might expect. And since many of the buildings in town are located right on the banks of the river, to protect from flooding, the city's buildings are built atop concrete pillars. The mountains surrounding the city have kept it isolated and prevented much tourism or development, but despite that more than 450,000 call Yanjin home today.

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