Pennsylvania has 3 of the 50 cities with the most green space per capita

Green space is beneficial anywhere, but especially in concrete jungles like those found in many U.S. cities. The World Health Organization reports that green areas are essential to both the ecosystem and the mental health of citizens; though the color is fading quickly in urban areas that are cutting down trees and rapidly building on open space. There are, however, some cities across America that are fighting hard to keep green space within their borders.

Using data from the Organization for Economic Co-operation and Development, analyzed by the United Nations Office for the Coordination of Humanitarian Affairs, Stacker considered the 70 U.S. cities with the most green space per capita and then ranked the top 50 by the green space areas devoted to parks and urban regions.

Read on to see which cities in your state made the list, or see the national story here.

#34. Pittsburgh

- Green space per capita: 8,119 sq. ft.
- Population: 1.4 million

Parks like Hartwood Acres with a 31-room mansion and 15 miles of trails make up some of Pittsburgh's green space. White Park, with some of the city's oldest trees, and Deer Lakes, with year-round fishing, are two more of Pittsburgh's prime green space spots. But it may be Mellon Square Park that's most appreciated for its green space, since "the 1.37-acre area is a perfect refuge to relax from the hustle and bustle of downtown's office-goers (or at least sit somewhere more scenic than your desk)," according to Fitt Pittsburgh.

#25. Philadelphia

- Green space per capita: 16,324 sq. ft.
- Population: 1.6 million

Home to Green Space Community Development Corporation, Philadelphia takes open space preservation seriously. They even create "parks in the sky" with rooftop lawns like Cira Green. Other popular parks in the City of Brotherly love include Glendinning Rock Garden, with a pond and waterfalls, and Benjamin Rush with 275 acres of community gardens, hiking trails, and bike paths. Fairmount Park is one of Philly's biggest patches of green space with 9,200 acres including free waterfront yoga classes and miles of running trails.

#16. Harrisburg

- Green space per capita: 23,519 sq. ft.
- Population: 560,849

Harrisburg turns sinkholes into green space, according to ABC27 news. The cost of an upcoming sinkhole restoration project is $6.5 million. While federal, state, and local officials are redeveloping holes into lawns, the Capital Area Greenbelt Association maintains the Trail, a 20-mile loop around Harrisburg and through Riverwood and Reservoir Parks. Another popular Harrisburg park is Five Senses Garden, which was created to help visitors explore their powers of sight, hearing, taste, smell and touch.

Some cities have gotten creative in constructing green space within their boundaries. Houston, Nashville, and Des Moines, Iowa, are among the many cities putting large green spaces on public rooftops. Atlanta even has plans to cover some of its highways with parks.

The former commissioner of the New York City Department of Parks and Recreation Adrian Benepe promotes the 10-Minute Walk campaign, an initiative to have a park within a 10-minute walk in all U.S. cities by 2050. Now the senior vice president for the Trust for Public Land, Benepe points to how green space helps the ecosystem. "When I see a tree, I see the work of God because a tree is a remarkable machine," Benepe said. "It does extraordinary things in exchange for very little."

What's more, the health benefits of parks and green spaces in cities are numerous, according to The National Recreation and Park Association. Large parks promote active living, which can reduce the risk of diabetes and heart disease, while research shows even small parks can reduce stress and improve creativity and mental health.

To learn more about which cities made the top of the list, keep reading below.

Cities with the most green space per capita

#1. Minneapolis, MN: 105,843 sq. ft. per capita
#2. Kansas City, MO: 93,349 sq. ft. per capita
#3. Cincinnati, OH: 67,723 sq. ft. per capita
#4. Washington, DC: 63,138 sq. ft. per capita
#5. Nashville, TN: 57,699 sq. ft. per capita