The San Juan archipelago is made up of over 400 islands and rocks, some only visible during low tide. They"re scattered across the Salish Sea between Washington state and Vancouver Island, British Columbia. No bridges connect the San Juans to the mainland, but four of the largest islands—San Juan, Orcas, Lopez, and Shaw—are accessible via the Washington State Ferries system. Tourists come to the islands to take in the stunning coastal views, catch a glimpse of resident orcas, and partake in many outdoor activities, such as sea kayaking, biking, and hiking.