The Mauna Kea Trail, also known as the Humuʻula Trail, is a hiking route leading from the Onizuka Center for International Astronomy to the summit of Mauna Kea, the highest volcano on the island of Hawaiʻi. The trail is a long, unmaintained dirt and scree path with two short road sections, about at the beginning and about near the summit. Cairns and reflective posts mark the route above .