The Park(ing) Day event takes place every year on the third Friday in September. Several of the makeshift parks appeared on Friday in Washington, D.C., including a location less than a mile from the White House.
Organizers say they stopped tracking numbers of participants, but they point to 2011, when they said "parks" took over parking spaces in 162 cities, 35 countries and six continents.
"PARK(ing) Day has amazingly established itself as a global event," the website says of the decision to stop tracking participation.
"From here on out, we’d rather focus on the quality or PARK installations and tactics for converting temporary action into long-term structural change," the website said. "Too many folks seemed overly-focused on the quantity of PARKs, and we’d like to shift the discussion toward the quality of urban public space."