 East of US 206/CR 533, the route enters Rocky Hill, where the name becomes Washington Street, and passes wooded residential areas, intersecting CR 605 in the center of the community.From this point, CR 518 enters woodland and crosses the Millstone River, where it enters Franklin Township and becomes Georgetown-Franklin Turnpike.Immediately following the Millstone River, the road crosses the Delaware and Raritan Canal and reaches the CR 603 intersection.