In the evening, I went to Mauna Kea - Snow Mountain to watch the stars and sunset. The rugged lava landscape on both sides of the highway reminds us all the time that we are on an active volcanic island. Mauna Kea, 13,796 feet (4,205 meters) above sea level, was once a glacier and the highest mountain on Hawaii's Big Island. If you count the part submerged in the sea, it will be over 10,000 meters high and become the highest mountain in the world - nbsp.