1911 Encyclopædia Britannica/San Juan Islands
SAN JUAN (or Haro) ISLANDS, an archipelago (San Juan, Orcas, Shaw, Lopez, Blakely, Cypress, &c.) lying between Vancouver Island and the mainland of North America. These islands were for many years the subject of dispute between the British and the United States governments, and were finally assigned to the latter country by the arbitration of the emperor of Germany (on the 21st of October 1872). Geographically the cluster certainly belongs to the mainland, from which it is separated by Rosario Strait, generally much under 50 fathoms in depth, while Haro Strait, separating it from Vancouver Island, has depths ranging from 100 to 190 fathoms. In 1873 the islands, formerly considered part of Whatcom county, Washington, were made the separate county of San Juan. Of the total area of 200 sq. m., about 60 are in San Juan, 60 in Orcas and 30 in Lopez.
See Papers relating to the Treaty of Washington, vol. v. (Washington, 1872), and the map in Petermann's Mitteilungen (1873).