San Juan Island
Location of San Juan Island in the San Juans | |
| Geography | |
|---|---|
| Location | Pacific Northwest |
| Coordinates | 48°32′N 123°05′W / 48.533°N 123.083°W |
| Archipelago | San Juan Islands |
| Area | 55.053 sq mi (142.59 km2) |
| Highest elevation | 1,080 ft (329 m) |
| Highest point | Mount Dallas |
| Administration | |
United States | |
| State | Washington |
| County | San Juan County |
| Largest settlement | Friday Harbor (pop. 2,162) |
| Demographics | |
| Population | 6,894 (2010 ) |
| Pop. density | 47.84/km2 (123.91/sq mi) |
San Juan Island is the second-largest and most populous of the San Juan Islands in northwestern Washington, United States. It has a land area of 142.59 km2 (55.053 sq mi) and a population of 8,632 as of the 2020 census.
Washington State Ferries serves Friday Harbor, which is San Juan Island's major population center, the San Juan County seat, and the only incorporated town in the islands.