New York's High Line has received lots of attention over the last few years, but it was actually inspired by this elevated railroad park in Paris.

The nearly three-mile trail, opened in 1993, was built on a former railway that was active from 1859 to 1969. The elevated portion -- one of the first elevated parks in the world -- stretches for about a mile. It's built on stone viaducts, the arches of which are now filled with small shops and cafes. The park then drops to street level, at times passing through tunnels.

The entire park is draped in lush vegetation, with some breaks offering commanding views of the city. The park is fully enclosed when passing near office or residential buildings.