Each direction of the parkway crosses Cabin John Creek before the roadways come together to pass under the Union Arch Bridge, which carries the Washington Aqueduct and MacArthur Boulevard.

The Cabin John Parkway crosses Cabin John Creek again before continuing north as a four-lane freeway with a speed limit of 55 mph (89 km/h) through a forested corridor paralleling the creek.

After crossing Booze Creek, the two directions of the parkway divide toward their terminuses at I-495 (Capital Beltway) in Bethesda.

[1][2] The Cabin John Parkway is maintained by the Maryland State Highway Administration and has an internal designation of Interstate 495X (I-495X).

[1] The Cabin John Parkway is a part of the National Highway System as a principal arterial for its entire length.