The Keystone Harbor Association was established in 1936 for the purpose of securing the construction of a ferry harbor near Fort Casey on Whidbey Island in Washington state. Mr. Luther Weedin served as president of the association and Mr. L.A. Wanamaker was the secretary. The goal was to provide a year round inland harbor that would accommodate ferries, tug boats, and other crafts, particularly the ferry running from Port Townsend to Keystone. The members of the association and their supporters saw the establishment of a harbor at Keystone as an important project in developing traffic between the North Puget Sound counties and British Columbia.

The Association garnered support from associations, clubs and businesses throughout the region such as the State Federation of Commercial Clubs, the State Good Roads Association, and the State River and Harbor association, as well as U.S. Senator Lewis B. Schwellenbach, who was instrumental in bringing the Association's proposals and research to the attention of the War Department. In 1938 the War Department corps of engineers concluded that the cost outweighed the benefits of a harbor at Keystone and ruled unfavorably in support of the project. The Keystone Harbor Association gathered more research supporting their project and tried for a War Department board of review hearing in 1940. Again the War Department ruled unfavorably. Despite these setbacks the Keystone Harbor was constructed by the U.S. Government in 1948.