A state highway to be known as state route number 20 north is established as follows:
Beginning at a junction with state route number 20 in the vicinity southeast of Anacortes, thence northwesterly to the state ferry terminal at Anacortes; also
From the state ferry terminal at Anacortes via the state ferry system to the state ferry terminals at Lopez Island, Shaw Island, Orcas Island, and Friday Harbor.
RCW 47.17.081