Mauna Kea Is Taller Than Everest, Base to Peak

Measured from its base on the ocean floor, Mauna Kea in Hawaii rises over 10,000 meters.
Everest wins on height above sea level, at about 8,849 meters. But most of Mauna Kea sits underwater, and its total height from base to summit is greater than Everest’s height above the sea.
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The US Geological Survey and NOAA both describe Hawaiian volcanoes in these terms.