The route is 10.0 miles (16.1 km) long, stretching north from an intersection with New York State Route 32 (NY 32) in the hamlet of Central Valley to a junction with NY 218 in the town of Cornwall, just west of the village of Cornwall-on-Hudson.

The northern terminus of CR 9 was originally located at Quaker Avenue in Cornwall, then designated as part of New York State Route 307.

The road continues, passing Filters Lake and Central Valley Golf Club.

Soon afterwards, CR 9 passes through a large patch of forests, which also covers parts of West Point Military Academy.

[1] Smith Clove Road continues, passing forests to the east and homes to the west.

[1][4] The original northern terminus of CR 9 was at the intersection of Quaker Avenue, Angola Road, and Main Street in Cornwall.

[citation needed] On January 9, 1980, the NY 307 designation was removed from the entirety of its routing.