5 mi. NE of village of Cape Fanshaw, 75 mi. E of Sitka, Coast Mts.
Named in 1887 by Lieutenant Commander C. M. Thomas, U.S. Navy (USN), for Rear Admiral J. A. Dahlgren, U.S. Navy (USN). The name was published in 1888 by U.S. Coast and Geodetic Survey (USC&GS) on Chart 705.