French Frigate Shoals

Other names: Kanemiloha'i

Geography: Largest atoll in the Hawaiian Islands, with 20-mile-long crescent-shaped reef, a dozen sand bars.

Distance from Honolulu: 560 miles

Highest point: 120 feet (La Perouse Pinnacle); sandbars to 6 feet

Type of island: Atoll, with one visible remnant of its volcanic origin, La Perouse Pinnacle.

Dry land: 67 acres

Coral reefs within 13.8 miles: 232,894 acres

History: During World War II, the U.S. military dredged a channel to one of the sand bars within French Frigate Shoals, and built up the sandbar with the dredged coral rubble. A runway was built for military aircraft, and the site was later a Coast Guard station. Today, the Fish and Wildlife Service keeps a small staff on the island to oversee the birds, seals, turtles and other wildlife.