Mauna Kea ( or , ), also called Mauna a Wakea in Hawaiian culture, is a dormant volcano on the island of Hawaii. Standing above sea level, its peak is the highest point in the state of Hawaii. Much of the mountain is under water; when measured from its oceanic base, Mauna Kea is over tall, taller than Mount Everest. Mauna Kea is about a million years old, and has thus passed 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 rougher 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 6,000 to 4,000 years ago and is now considered dormant.