PA 56 starts at the intersection of Industrial Boulevard and 9th Street in New Kensington, Westmoreland County; this is also the eastern end of the C.L.

In New Kensington, PA 56 first heads south along Industrial Boulevard before turning east onto 7th Street where it first encounters a short city-maintained section of road before transitioning back to state maintenance.

[2][failed verification] PA 56 ends its concurrency with US 119 in Homer City and continues east on a two-lane road.

The route then enters Westmoreland County again briefly, passing through its extreme northeastern corner.

[2][failed verification] PA 56 travels through the heart of the West End section of Johnstown on two-lane city streets.

It eventually exits US 219 at Scalp Avenue, the original interchange, and continues east toward Windber.

The descent down the eastern slope contains a dangerous hairpin curve that has been the site of many accidents over the years.

The route's western terminus also marks the end of its parent, as each formulate a different way of travel for those who have crossed the C.L.