The islands were fortified with numerous coastal artillery batteries during World War II, but did not experience any combat. Remains of these fortifications can be found on the island of Wakamiyajima, north of the main Iki Island. On November 18, 1948, Lt. William Downham, from the USAF 36th Fighter Group stationed at Ashiya Air Field, experienced engine failure in his North American P-51 Mustang while patrolling the Korea Strait between Japan and the Korean Peninsula. He successfully parachuted onto Iki Island.