Despite the chilly temperatures Sunday, thousands turned out turned out at the Metroparks Zoo in Cleveland for the cityâs annual Earth Day Festival. Organizers say Clevelandâs Earthfest is the stateâs largest environmental education event and is believed to be the longest running earth day celebration in the country. Scott Sanders, Executive Director of Earth day Coalition, says environmentalism has come a long way since the Cuyahoga River fire ushered in the clean air act and other environmental regulations in the 70s. He says one of the main areas of progress is the corporate community becoming more engaged with environmental initiatives. "I think weâre just seeing the beginning of that, the tip of the ice berg in terms of large scale partnerships and collaborations, public and private partnerships that really cross borders," Sanders said. This yearâs Earthfest theme was sustainability, with a focus on how people can by locally grown and produced food. It featured more than 150 education and product exhibits and, and more than a hundred live music acts performed throughout the zoo grounds.