City of SeattleFreeway ParkThe answer is 62 (that they know of), says the city in this report.This handy PDF has a list of some of them–and whether or not they’re open to the public for a nice, daytime activity that combines the tranquility of parks with the adrenaline rush and awesome view that come from standing on a roof.You can tour one on top of the Ballard Library. The Puget Sound Blood Center has one that you can’t see (what do they use it for?). You may have walked right through Freeway Park without realizing it’s a rooftop garden. Your apartment building might even have one (I’ve suspected that my building has a top-secret one)!According to My Ballard, Bastille even serves produce grown on the restaurant’s roof. How efficient.