Ryan Donahue of the Trust for Public Land says that it depends on age, health, time availability, quality of surroundings, safety, climate, and many other factors.
One problem with assessing how far people will walk to use a park is that most walkability studies are focused on commuters rather than park users who have a mix of motivations. However, it does seem that the quarter-mile standard used to assess the walkability of transit stations is mostly applicable to parks as well:
"...research supports the validity of both quarter-mile and half-mile distance goals, depending on perceptions of the built environment, safety, and time constraints. Of course, people's preferences and habits are only part of the equation for planners, who must also take into account the cost effectiveness of expanding the park system versus improving current parks or focusing on connectivity."
FULL STORY: Pedestrians and Park Planning: How Far Will People Walk?

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Restaurant Patios Were a Pandemic Win — Why Were They so Hard to Keep?
Social distancing requirements and changes in travel patterns prompted cities to pilot new uses for street and sidewalk space. Then it got complicated.

Map: Where Senate Republicans Want to Sell Your Public Lands
For public land advocates, the Senate Republicans’ proposal to sell millions of acres of public land in the West is “the biggest fight of their careers.”

Maui's Vacation Rental Debate Turns Ugly
Verbal attacks, misinformation campaigns and fistfights plague a high-stakes debate to convert thousands of vacation rentals into long-term housing.

San Francisco Suspends Traffic Calming Amidst Record Deaths
Citing “a challenging fiscal landscape,” the city will cease the program on the heels of 42 traffic deaths, including 24 pedestrians.

California Homeless Arrests, Citations Spike After Ruling
An investigation reveals that anti-homeless actions increased up to 500% after Grants Pass v. Johnson — even in cities claiming no policy change.
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