Gardner Pinnacles

Other names: Puhahonu, Gardner Island

Geography: Two rock outcroppings are all that's left of a former volcanic island.

Distance from Honolulu: 690 miles

Highest point: 190 feet

Type of island: Remnant volcanic island

Acreage dry land: 5 acres

Coral reef within 13.8 miles: 291,056 acres

History: Whaling captain Joseph Allen in 1820 sighted the rocks, which at that time were not found on Western charts.

Biology notes: Gardner has more species of fish along its undersea shelves than are found at the larger rocky islands of Nihoa and Mokumanamana, and has one of the highest diversities of marine life in the entire Northwestern Hawaiian Islands. It's not the same for plants, however, since only a single species, a purslane, clings to its rocks.