US Environmental Protection Agency
Epa: The Spirit of the First Earth Day
This article is an in-depth description of the first Earth Day, and includes the impact the demonstration had on the environmental movement.
Cleveland State University
Cleveland State University Library: Memory Project: Cuyahoga River Exhibition
Photographs and documents that explain the river-management practices of the city of Cleveland with respect to the Cuyahoga River, including efforts to straighten its path.