Route 4 and Route 2 South of Lusby, Maryland

Route 4 meets with Maryland Route 2 (Solomons Island Road) near the town of Sunderland at the Lower Marlboro Road junction. "Route 4/2" continues south for 26.9 miles, and both are known as Solomons Island Road.

The road continues running nearly due south, intersecting the western end of Maryland 575 north of Huntingtown and the western end of Maryland 263 south of same. South of Prince Frederick the road gains a second name, the Louis L. Goldstein Highway.