It may be no surprise that many cities are stepping up their eco-friendly practices, but there are some unexpectedly green cities that are really on the right path.

Austin, Texas, is fast becoming one of the greener cities in the U.S.

Here, you’ll find 26 interconnected greenbelts, which means you can walk or bike across the city without leaving the park.

And you can go sightseeing the eco-friendly way with a company called Clean Air Limo.

In Chicago, Mayor Daley is transforming rooftops into sustainable beauty—there are more than two million feet of sky-high gardens in the Windy City.

Even Sin City has some green initiatives.

Las Vegas is the first city in the West to use hydrogen-powered buses, and Lucky Cab Company uses hybrids for 20 percent of its fleet.

The MGM Mirage is constructing Project CityCenter, a development that will be the largest LEED-certified project in the country.

Check out our Responsible Travels category for more helpful hints.

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