Kīlauea is the youngest and southeastern most volcano on the Island of Hawai‘i. Topographically Kīlauea appears as only a bulge on the southeastern flank of Mauna Loa, and so for many years Kīlauea was thought to be a mere satellite of its giant neighbor, not a separate volcano. However, research over the past few decades shows clearly that Kīlauea has its own magma-plumbing system, extending to the surface from more than 60 km deep in the earth.
In fact, the summit of Kīlauea lies on a curving line of volcanoes that includes Mauna Kea and Kohala and excludes Mauna Loa. In other words, Kīlauea is to Mauna Kea as Lō‘ihi is to Mauna Loa. Hawaiians used the word Kīlauea only for the summit caldera, but earth scientists and, over time, popular usage have extended the name to include the entire volcano.
Kīlauea is the home of Pele, the Hawaiian volcano goddess. Hawaiian chants and oral traditions tell in veiled form of many eruptions fomented by an angry Pele before the first European, the missionary Rev. William Ellis, saw the summit in 1823. The caldera was the site of nearly continuous activity during the 19th century and the early part of the 20th century. Kīlauea ranks among the world's most active volcanoes and may even top the list.
Since 1952, Kīlauea has erupted 34 times. From 1983 to 2018 eruptive activity was nearly continuous along the volcano's East Rift Zone. At the summit, a vent within Halema‘uma‘u hosted an active lava pond and vigorous gas plume from 2008 to 2018. In 2018, the decades-long continuous activity on the East Rift Zone ended, and the summit lava lake drained following an intrusion into, and eruption from, Kīlauea's lower East Rift Zone. That was Kīlauea's largest eruption in at least 200 years and was accompanied by the largest summit collapse for the same time period.