SR 612 traveled on what is now West 130th Street in western Cuyahoga County.

The route began at SR 82 on the Strongsville–North Royalton line.

It continued northward, traversing along the borders of Stongsville, North Royalton, Middleburg Heights, Parma, Brook Park, and Parma Heights, before intersecting SR 17 on the border of Cleveland and Parma.

The highway continued further north to SR 10 in Cleveland, where it terminated.

[4] The route was deleted from the state highway system in 1951.