I went to college in New York City in the early 1970s. The crime rate was very high during that period and, living as a poor student in underserved neighborhoods, I was personally a victim of violent crime on multiple occasions. Apart from Central Park, well- tended greenspace, pocket parks or tree-lined streets were a rare commodity. As students we felt this deficit at our core. Columbia University lies alongside Morningside Park and the possibility that a new gymnasium was going to be built there, and diminish one of Harlem’s amenities, sparked a campus protest that changed the culture of university campuses for decades. What we knew then and still know now is that access to nature is critical to quality of life. Most of us, when asked to recall our most poignant and pleasant childhood memory, place it in an outdoor setting – hanging out in a makeshift tree fort or eating ice cream on a building stoop in the sun. This affinity for nature is called biophilia. As we evolved, we benefited from focusing on nature. Attending to sources of water and food and environments that helped us avoid saber-toothed tigers were critical to survival.

This evolutionary prerogative has been demonstrated by environmental psychologists who have found that access to nature has stress-reducing effects and increases life satisfaction. But there is another interesting implication. Recent researchers have concluded that the presence of parks and other greenspace may also reduce urban crime.

While people may not think of the physical environment as playing a role in mitigating negative social behaviors, evidence strongly suggests that it does. A multidisciplinary team from the University of Pennsylvania, US Department of Agriculture – Forest Service and Washington State University found that blight remediation of abandoned lots in Philadelphia significantly reduced crime. And, if saving human life and the reducing the associated personal and societal loss isn’t impetus enough, there are fiscal benefits to reductions in violent crime.

The research team also determined that taxpayer returns on investment for the prevention of firearm violence were $26 for every dollar spent on remediation. Relatedly, the National Institutes of Health estimates that costs for a single murder, such as economic loss of victims, police service, adjudication, and corrections program expenses, are almost $1.3 million.

Some might argue against expenditures on parks and greenspace as these investments are perceived to play less of a role in mitigating violence than social programs. While social initiatives are significant, the contribution of the physical environment cannot be denied. Good public spaces support desirable behaviors and inappropriate public spaces provide the opportunity for criminal behavior. The provision of outdoor amenities is a social program.

The public understands these issues. In a recent study by Cornell University researchers, 80 percent of respondents agreed that the environment had an impact on behavior. In this study researchers found that two-thirds of the respondents who have attractive nature sights in their vicinity also perceived their neighborhood to be a place where people look out for one another. This outcome speaks to the strong relationship between greenspace and social cohesiveness.

Why is greenspace so powerful? The presence of parks suggests that the community is important to the city government and creates civic pride. As a result, parks may contribute to community adhesion.

There are many other reasons. Outdoor recreational spaces provide the opportunity for youth activities in a venue made safe by public surveillance and thereby may deter gang violence. Outdoor gathering spaces provide the opportunity for interaction among neighborhood members, which increases familiarity and mutual investment in well-being. Parks provide the opportunity for exercise, which enhances our mental acuity and may reduce obesity.

Additionally, based on the studies discussed previously, nature may simply have a calming impact on our state of mind. Who can deny the healing effect of a walk through a park? Rock Creek Park in Washington, DC, which is visited more frequently than the White House, is a testimonial to this.

The designers of cities are not interested in producing “just another pretty face.” They want to help change the world and make it a safer and healthier place. To accomplish this goal we must engage in efforts that allow for the remediation of vacant lots, contribute to street tree planting programs, support the maintenance and enhancement of existing greenspaces, and set aside property for the development of future parks. We must hold on tenaciously to our existing parks, both urban and rural, as an investment in the health and well-being of our society.