Artists and environmental activists will create temporary parks in the streets of Pittsburgh tomorrow. But these parks will only be as big as a parking space -- and will cost 25 cents per half hour to maintain. Pittsburgh is one of several cities worldwide taking part in "PARK(ing) Day." The idea originated in San Francisco in 2005 and is now a recognized international event. Pittsburgh has been taking part in the project for the last three years. Local co-organizer Andrea Lavin Kossis expects this year to be the best yet. "The response has been overwhelming. We’re hoping to have over forty spaces and all sorts of organizations are involved," says Kossis. Organizers, including the Community Design Center of Pittsburgh, see the event as an opportunity for young artists to create temporary green spaces and make a peaceful, proactive pitch for more open space in urban centers. The event allows artists to be creative and encourages interaction among citizens walking the streets and those transforming parking spots. The spaces featured in this years PARK(ing) Day will be located throughout the city including Downtown, the North Side, South Side and East End, specifically on Penn Avenue.