Know what northeast Ohioans are sick of hearing about? Yep, you guessed it: the June 22, 1969, incident in which a polluted stretch of the Cuyahoga River, which empties into Lake Erie at Cleveland, caught fire. Here's the kicker: it wasn't the first, or worst, of the Cuyahoga's fires. With industrial waste pouring in, it caught fire many times starting in 1868, with the worst in 1952 (shown). Locals recall that the water was so toxic it would dissolve canoes. The good news: the fire helped spur the creation of Earth Day, the Environmental Protection Agency, and the Clean Water Act.