File:View of Mauna Kea from Pu'uokohala Heiau National Historic Site, Hawaii (4528800732).jpg

Mauna Kea is a volcano on the island of Hawaii. Standing 13,796 ft (4,205 m) above sea level, its peak is the highest point in the U.S. state of Hawaii. However, much of Mauna Kea is below sea level; when measured from its oceanic base, its height is 33,500 ft (10,200 m)—more than twice Mount Everest's base-to-peak height of 3,650 to 4,650 meters (11,980 to 15,260 ft). Mauna Kea is about one million years old, and thus past the most active shield stage of life hundreds of thousands of years ago. In its current post-shield state, its lava is more viscous, resulting in a steeper profile. Late volcanism has also given it a much smoother appearance than its neighboring volcanoes: contributing factors include the construction of cinder cones, the decentralization of its rift zones, the glaciation on its peak, and the weathering effects of the prevailing trade winds. Mauna Kea last erupted 4,600 years ago. According to the USGS, as of January 2012, the Volcanic Alert Level is "Normal".

In Hawaiian mythology, the peaks of the island of Hawaii are sacred, and Mauna Kea is one of the most sacred. An ancient law allowed only high-ranking tribal chiefs to visit its peak. Ancient Hawaiians living on the slopes of Mauna Kea relied on its extensive forests for food, and quarried the dense volcano-glacial basalts on its flanks for tool production.

With its high altitude, dry environment, and stable airflow, Mauna Kea's summit is one of the best sites in the world for astronomical observation, and one of the most controversial. Since the creation of an access road in 1964, thirteen telescopes funded by eleven countries have been constructed at the summit. The Mauna Kea Observatories are used for scientific research across the electromagnetic spectrum from visible light to radio, and comprise one of the world's largest facilities of their type. In April 2013, the Thirty Meter Telescope project was approved, and will be the largest telescope ever built. Their construction on a "sacred landscape", replete with endangered species and ongoing cultural practices, continues to be a topic of debate and protest. Studies are underway to determine their effect on the summit ecology, particularly on the rare Wēkiu bug. It was designated a National Natural Landmark in 1972.

en.wikipedia.org/wiki/Mauna_kea