Complex sentence: Chesapeake and Ohio Canal, and the Potomac River while heading east along a narrow corridor between the river and several north--south ridges where the freeway has a pair of partial interchanges with MD 615 (Millstone Road).
Split into simpler sentences: Chesapeake and Ohio Canal, and the Potomac River while heading east along a narrow corridor between the river and several north--south ridges. Within this corridor, the freeway has a pair of partial interchanges with MD 615 (Millstone Road).