Keystone Jetty (Fort Casey Underwater Park)

Washington's other underwater state park, along the rock jetty protecting Keystone Harbor at Fort Casey State Park on Whidbey Island, next to the Coupeville-Port Townsend ferry landing. The jetty boulders are plastered with anemones and nudibranchs and shelter wolf eels, octopus and big lingcod, with about 55-60 ft of depth at the jetty tip. Admiralty Inlet currents sweep the site hard, so it is strictly a slack-water dive planned with Admiralty Head current predictions, and divers must never round the jetty into the active ferry lane.