Saddle Road to Mauna Kea Access Road

The Mauna Kea Access Road climbs from 6,500 feet at Saddle Road through the Mauna Kea State Recreation Area to the 13,796-foot summit, passing through distinct ecological zones from tropical scrubland to alpine desert. The paved road becomes graded cinder at Onizuka Center for International Astronomy around 9,200 feet, where most rental cars turn back due to insurance restrictions. The final 4.5 miles to the summit pass through otherworldly red cinder fields that NASA uses for Mars rover testing.

This moderate route requires 4WD for the upper section and decent ground clearance for loose volcanic cinder. Weather can shift rapidly from clear to whiteout conditions above treeline, and altitude sickness affects some visitors. Best driven in dry conditions April through October, though snow can occur year-round above 12,000 feet. The payoff is world-class stargazing at Lake Waiau and standing atop the Pacific’s highest peak among billion-dollar telescopes.