U.S. Route 101
The nearly highway's northern terminus is in Tumwater, Washington: the route remains along the Olympic Peninsula's coastal perimeter west, north, and east; the northernmost point on the highway is in Port Angeles. The southern terminus of US 101 is in Los Angeles at the East Los Angeles Interchange, the world's busiest freeway interchange.
New York State Route 101
In Port Washington, NY 101 passes Nassau Knolls Cemetery and narrows to become a four-lane undivided highway as it enters the center of the hamlet. It proceeds north–south through downtown, passing several blocks of commercial buildings and Paul D. Schreiber Senior High School ahead of a junction with Main Street. North of this point, the surroundings of NY 101 become more residential as the route narrows to two lanes and passes into the village of Sands Point. NY 101 ends shortly afterward at an intersection with Astor Lane, at which point Port Washington Boulevard is continued by Middle Neck Road and designated as CR 101.