Mauna Kea is the highest underwater mountain when measured from base to summit. The mountain is located in the Island of Hawaii. It is the highest point in the state of Hawaii. The mountain peaks at 4,207 meters (13,802 feet).
Mauna Kea is also the tallest mountain in the wall although the summit of Mount Everest above sealevel is higher than that of Mauna Kea above sea level but when considering the summit above sea level and the base underwater, Mauna Kea is the tallest. Measuring from the base on the ocean floor, Mauna Kea is about 10,000 meters (33,000 feet).