Hawaiʻi (island)



Hawaii, sometimes written Hawaii, is the largest island in the United States, located in the state of Hawaii, the southernmost state in the union. It is the southeasternmost of the Hawaiian Islands, a chain of volcanic islands in the North Pacific Ocean. With an area of, it has 63% of the Hawaiian archipelago's combined landmass. However, it has only 13% of the archipelago's population. The island of Hawaii is the third largest island in Polynesia, behind the North and South Islands of New Zealand.
The official name of the island is Island of Hawaii to distinguish it from the state. It is also referred to as The Big Island, due to its size relative to the other islands. In Hawaiian, the island is sometimes called Moku o Keawe. The word keawe has several meanings. One definition, "southern cross", is said to be the name of an ancient chief. Another definition is "the bearer".
Hawaii County is the local administrative unit. As of the 2020 census, the population was 200,629. The county seat and largest city is Hilo. Hawaii County has no incorporated cities.

History

Hawaii is allegedly named after Hawaiiloa, a legendary Polynesian navigator who is said to have discovered the island. Other accounts attribute the name to the legendary realm of Hawaiki, a place from which some Polynesians are said to have originated, the place where they transition to in the afterlife, or the realm of the gods and goddesses. The indigenous Hawaiian name of the island was originally rendered and published as "Owyhee" or "Owhyhee".
It is uncertain when Hawaii was first discovered by humans. Early archaeological studies suggested that Polynesian explorers from the Marquesas Islands or Society Islands may have arrived in the Hawaiian islands as early as the 3rd century AD, possibly with a second wave arriving from Tahiti around 1100. However, more recent analyses suggest that the first settlers arrived around 900–1200 AD.
File:Ahu A Umi Heiau.jpg|thumb|300px|The Ahu-a-Umi Heiau, built for Umi-a-Līloa in the Kona District
Oral tradition holds one of the most famous aliinui of Hawaii to be Umi-a-Līloa, who united the island by force. He was the illegitimate son of Līloa, aliinui of Hawaii who ruled from Waipio Valley in the Hāmākua district. When Līloa died, the island passed to Umi's half-brother Hakau. However, Umi attacked and killed Hakau along with the alii who served him, winning control of Hāmākua. He then proceeded to conquer the rebelling districts of Hilo, Puna, Kaū, and Kona. He placed the seat of his new government in Kailua in the Kona district.
In 1779, Captain James Cook made his second voyage to the Hawaiian islands, anchoring in Kealakekua Bay on the island of Hawaii. He spent several weeks there, meeting and trading with locals and readying his ships for a planned trip to the Arctic. The Hawaiians received him hospitably, considering him to be an incarnation of the god Lono. Early in 1780, Cook departed. However, his ships were damaged in a storm immediately after setting sail, and he was forced to return to Kealakekua after only a week at sea. During this second anchoring, an altercation between the Europeans and the Hawaiians turned violent, resulting in the death of multiple people on both sides, including Cook himself. Peaceful relations were eventually restored with the crew of his ships, who departed for good later that month.
In 1780, the island of Hawaii was controlled by the aliinui Kalaniōpuu, a descendant of Umi-a-Līloa. On his death in 1782, he designated his son Kīwalaō as his heir. However, a feud between Kīwalaō and Kalaniōpuu's nephew Paiea Kamehameha soon escalated into a civil war. Kīwalaō was killed in the Battle of Mokuōhai later that same year, leaving control of the island divided between Kamehameha in the west, Kīwalaō's uncle and advisor Keawemauhili in the northeast, and Kīwalaō's half-brother Keōua Kūahuula in the south. The three chiefs, aided by Western ships and weapons, fought to a standstill for eight years until 1790, when Keōua defeated and killed Keawemauhili. In 1791 Kamehameha's men killed Keōua at a diplomatic meeting, leaving control of Hawaii to Kamehameha.
Kamehameha went on to conquer the rest of the Hawaiian islands, consolidating his control in 1810 with the peaceful surrender of Kaumualii, king of Kauai. He gave his new kingdom, and by extension the island chain itself, the name of his native island – the Kingdom of Hawaii.
In 1822, missionary William Ellis arrived and was one of a party that completed a tour of the island, descriptions of which were later published in his journal.
In July, 1898, Hawaii and all the Hawaiian islands were annexed by the United States, becoming the Territory of Hawaii. In 1905, the passage of the County Act established the County of Hawaii, providing the island with local government for the first time since 1810.

Geology and geography

According to the U.S. Census Bureau, the county has a total area of, of which is land and is water. The county's land area comprises 62.7 percent of the state's land area. It is the highest percentage by any county in the United States. Delaware's Sussex County comes in second at 48.0 percent, while Rhode Island's Providence County is third at 39.6 percent.
At its greatest dimension, the island is across. Measured from its sea floor base to its highest peak, Mauna Kea at is the world's tallest mountain, taller than even Mount Everest, since the base of Mount Everest is above sea level.
The most southern point of Hawaii, Ka Lae, is the southernmost point of the United States. The nearest landfall to the south is the Line Islands. To the northwest of the island of Hawaii is the island of Maui, whose Haleakalā volcano is visible from HawaiKau, Hawaii|i Island across the Alenuihāhā Channel.

Volcanism

The island of Hawaii is built from five separate shield volcanoes that erupted somewhat sequentially, one overlapping the other. These are :
Geological evidence from exposures of old surfaces on the south and west flanks of Mauna Loa led to the proposal that two ancient volcanic shields were all but buried by the younger Mauna Loa. Geologists now consider these "outcrops" to be part of Mauna Loa.
Based on geochemical and isotope differences in their eruptive products, Hawaiian volcanoes fall into two families. The differences are believed due to their separate magma systems. Hualālai and Mauna Loa are members of one family, while Kohala, Mauna Kea, and Kilauea are members of the other.
Because Mauna Loa and Kīlauea are active volcanoes, the island is growing. Between January 1983 and September 2002, lava flows added to the island. Lava flowing from Kīlauea destroyed several towns, including Kapoho in 1960 and again in 2018, and Kalapana and Kaimū in 1990. In 1987 lava filled in "Queen's Bath", a large, L-shaped, freshwater pool in the Kalapana area. Another 875 acres were added between May and July 2018 by the 2018 lower Puna eruption, with "Fissure 8" located within Leilani Estates subdivision being a primary source of the lava. Green Lake, the largest freshwater lake on the island, was covered by lava in that eruption as well as Ahalanui Beach Park and part of Isaac Hale Beach Park, the latter of which was inundated with black sand, rendering its boatramp unusable. Mauna Loa erupted briefly in 2022, 38 years after the prior activity.
Some geologists also count two undersea volcanoes in the base of the island. Māhukona off the northwest corner of the island has eroded below the ocean surface. Kamaehuakanaloa is under water southeast of Hawaii. It is an erupting seamount that has grown to reach below the ocean surface, and it is forecast to break the surface in 10,000 to 100,000 years.
The volcano Kilaueak, has had its 38th eruption on December 8th 2025. It began Saturday morning and sent lava shooting at least 1,000 feet into the air, according to the USGS. At one point, a "rare" triple fountain occurred: three lava fountains spewed from vents in the north and south cones. During these events, the USGS put a code orange in place, which indicates that an eruption is either likely or occurring, but with no, or minor, ash. There was also a warning of tephra, or hot glassy volcanic fragments, as well as pumice, scoria and reticulite, which can fall on the ground within one to three miles of the eruptive vents.

Great Crack

The Great Crack is an, and fissure in the island, in the district of Kaū. According to the United States Geological Survey, the Great Crack is the result of crustal dilation from magmatic intrusions into the southwest rift zone of Kīlauea. While neither the earthquake of 1868 nor that of 1975 caused a measurable change in the Great Crack, lava welled out of its lower in 1823.
Trails, rock walls, and archaeological sites from as old as the 12th century exist near the Great Crack. In August 2018, the National Park Service purchased nearly of private land adjacent to Hawaii Volcanoes National Park, claiming that the area had important geological features to be studied and preserved.

Hilina Slump

The Hilina Slump is a section of the south slope of Kīlauea that is moving away from the island. Between 1990 and 1993, Global Positioning System measurements showed a southward displacement of about per year. Undersea measurements show a "bench" that has formed a buttress and that this buttress may tend to reduce the likelihood of catastrophic detachment.

Earthquakes and tsunamis

On 2 April 1868, an earthquake with a magnitude estimated between 7.25 and 7.9 rocked the southeast coast of Hawaii. This was the most destructive earthquake in the Hawaii's recorded history. It triggered a landslide on Mauna Loa, north of Pāhala, killing 31 people. A tsunami claimed 46 more lives. The villages of Punaluu, Nīnole, Kāwāa, Honuapo, and Keauhou were severely damaged. The tsunami reportedly rolled over the tops of the coconut trees up to high, and it reached inland a distance of a quarter of a mile in some places.
On 29 November 1975, a section of the Hilina Slump dropped and slid toward the ocean. This movement caused a 7.2 magnitude earthquake and a tsunami. Oceanfront property was washed off its foundations in Punaluu. Two deaths were reported at Halape, and 19 other people were injured.
The island suffered damage from a tsunami caused by earthquakes in Alaska on 1 April 1946, and in Chile on 23 May 1960. Downtown Hilo was damaged by both tsunamis, with many lives lost. Just north of Hilo, Laupāhoehoe lost 16 schoolchildren and five teachers in the tsunami of 1946.
In March 2011, a 9.0 magnitude earthquake off the east coast of Japan again created a tsunami that caused minor damage in Hawaii. The estimated damage to public buildings was about US$3 million. In the Kona area this tsunami washed a house into Kealakekua Bay, destroyed a yacht club and tour boat offices in Keauhou Bay, caused extensive damage in Kailua-Kona, flooded the ground floor of the King Kamehameha Hotel, and temporarily closed the Kona Village Resort.
In early May 2018, hundreds of small earthquakes were detected on Kīlauea's East Rift Zone, leading officials to issue evacuation warnings. On 3 May 2018, the volcano erupted in Puna after a 5.0 earthquake earlier in the day, causing evacuations of Leilani Estates and Lanipuna Gardens subdivisions. A seemingly related 5.3 magnitude quake and a subsequent 6.9 magnitude earthquake occurred on 4 May.