Oʻahu (pronounced [oˈʔɐhu]) or Oahu /oʊˈɑːhuː/, known as “The Gathering Place,” is the third largest of the Hawaiian Islands; however, it is home to about two-thirds of the population of the US state of Hawaii, and is the home of Honolulu International Airport. The state capital, Honolulu, is on Oʻahu’s southeast coast. Including small close-in offshore islands such as Ford Island and the islands in Kaneohe Bay and off the eastern (windward) coast, it has a total land area of 596.7 square miles (1,545.4 km2), making it the 20th largest island in the United States. Along with the rest of the Hawaiian Islands, Oahu is one of the largest and northernmost islands of Polynesia.
In the greatest dimension, this volcanic island is 44 miles (71 km) long and 30 miles (48 km) across. The length of the shoreline is 227 miles (365 km). The island is the result of two separate shield volcanoes: Waiʻanae and Koʻolau, with a broad “valley” or saddle (the central Oʻahu Plain) between them.