Oahu is 44 miles (71 km) long and 30 miles (48 km) across. Its shoreline is 227 miles (365 km) long. Including small associated islands such as Ford Island plus those in Kāneʻohe Bay and off the eastern (windward) coast, its area is 596.7 square miles (1,545.4 km2), making it the 20th-largest island in the United States.[5]
The Island of Oahu in Hawaii is often nicknamed (or translated as) "The Gathering Place". The translation of "gathering place" was suggested as recently as 1922 by Hawaiian Almanac author Thomas Thrum. Thrum possibly ignored or misplaced the ʻokina because the Hawaiian phrase "ʻo ahu" could be translated as "gathering of objects" (ʻo is a subject marker and ahu means "to gather"). The term Oʻahu has no other confirmed meaning in Hawaiian.[6][7]
Oahu has been inhabited since at least the 3rd century A.D.[8] The 304-year-old Kingdom of Oahu was once ruled by the most ancient aliʻi in the Islands. The first great king of Oahu was Maʻilikūkahi, the lawmaker, who was followed by generations of monarchs. Kualiʻi was the first of the warlike kings and was succeeded by his sons. In 1773, the throne fell upon Kahahana, the son of Elani of Ewa. In 1783, Kahekili II, King of Maui, conquered Oahu, deposed the reigning family, and made his son, Kalanikūpule, king of Oahu, turning Oahu into a puppet state. Kamehameha the Great conquered Kalanikūpule's forces in the Battle of Nuʻuanu. Kamehameha founded the Kingdom of Hawaii with the conquest of Oahu in 1795. Hawaii was not unified until King Kaumualiʻi surrendered the islands of Kauai and Niihau in 1810. Kamehameha III moved his capital from Lahaina, Maui to Honolulu, Oahu in 1845. ʻIolani Palace, built later by other members of the royal family, still stands, and is the only royal palace on American soil.
On January 19, 1778, Oahu was the first of the Hawaiian Islands to be sighted by Captain James Cook during his third voyage of discovery.[9] This was the first recorded encounter of the Hawaiian Islands by non-Polynesian people. Cook bypassed Oahu, landing instead at Kauai before continuing his original mission to explore the coast of North America. The next year, on February 27, 1779, Cook's second in command, Captain Charles Clerke, became the first recorded non-Polynesian to visit Oahu when he landed at Waimea Bay. Earlier that month, Cook had been killed at Kealakekua Bay on the island of Hawaii when a dispute with the local people turned violent.[10] Clerke's visit to Oahu was brief and the expedition's two ships left Waimea Bay the same day after finding it difficult to obtain fresh water.[11] In the years following Cook and Clerke's visits, the publication of several books relating to their voyage attracted other European and American explorers, traders, and whalers, who found the islands a convenient harbor and source of supplies. This introduced disease, mosquitoes, and aggressive animals. Although indirect, simple exposure to these foreign species caused permanent damage to the Native Hawaiian people and environment.
The Imperial Japanese Navy's attack on Pearl Harbor, Oahu on the morning of December 7, 1941, brought the United States into World War II. The surprise attack was aimed at destroying the American will to fight and forcing the US to sue for peace. They attacked the Pacific Fleet of the United States Navy and its defending Army Air Forces and Marine Air Forces. The attack damaged or destroyed 12 American warships, destroyed 188 aircraft, and killed 2,335 American servicemen and 68 civilians (of those, 1,177 were the result of the destruction of the USS Arizona alone).[12][13]
Oahu became a tourism and shopping haven after World War II. Over five million visitors (mainly from the contiguous United States and Japan) flock there every year.[14]
Oahu is known for having the longest rain shower in recorded history. Kāneʻohe Ranch reported 247 straight days of rain from August 27, 1993, to April 30, 1994. The average temperature in Oahu is around 70–85 °F (21–29 °C). The island is the warmest from June through October. The winter is cooler, but still warm, with an average temperature of 68–78 °F (20–26 °C).
Volcanic Origins
Oahu rose above the sea during the Pliocene period from 4 million years ago when volcanoes erupted and formed the peaks from two shields. Then a period of extensive erosion followed, leaving the Wai‘anae and the young Ko‘olau Range as dormant volcanic ranges from remnants of volcanism.[citation needed]
Today, the island is composed of two separate shield volcanoes: the Waiʻanae and Koʻolau Ranges, with a broad valley or saddle (the central Oahu Plain) between them. The highest point is Kaʻala in the Waiʻanae Range, rising to 4,003 feet (1,220 m) above sea level.[16]