San Francisco ranked highest! Yet another reason it is wonderful to live here. Since this ranking system measures cities, Marin is not measured under Parkscore, but depending on who you listen too, the county is 50 to 90% open space, more than any other county in the SF Bay Area.
Quality of life (health, ability to concentrate, etc) is so much higher when there is somewhere green to enjoy, especially when you are also within walking, biking or a quick driving distance of the wonderful cultural amenities, and job opportunities, here.
*Thanks to Stacy Lamirand for "Chirp Score" Tweet tweet!