Maunaulu via Nāpau Trail

About This Trail

This is a 2.5-mile roundtrip hike across a raw 1969-74 lava landscape to a forested cinder cone, Pu'uhuluhulu. The first mile is deceptively technical—uneven, ankle-twisting lava terrain with zero shade. The final 1/4 mile is a sharp 210-foot climb that demands grit. Payoff: summit views of Mauna Loa, Mauna Kea, and the Pacific Ocean on clear days. Difficulty: Moderate intensity, high exposure. Bring extra water and high-ankle boots—this isn't a walk.

Highlights

Insider Tips

• The false-flat sections across the lava will trick your feet—ankle support matters; wear high boots • Don't stop at the saddle between lava flows—push to the cinder cone summit for the payoff views • Stay disciplined on the marked ahu trail; it's easy to veer off and get disoriented • The climb looks short but is steep and relentless—prepare mentally • Clear days (rare) give you Mauna Loa and Mauna Kea views; cloudy days block the summit view

Best Season to Hike

Year-round (park is open 24/7); cooler dry season (May-September) may be more comfortable

Family Info

The steep climb and rough terrain challenge small children. The 1/4-mile summit push is a lung-buster—hold hands on steep sections. Full sun exposure demands heat preparation. Ankle-twisting lava is tough on young hikers. Ages 8+ with hiking experience and good boots recommended.

What Hikers Say

Hikers report the lava terrain is much rougher than expected—ankle injuries are common. The climb to Pu'uhuluhulu is steep but short, with payoff views of Mauna Loa and Mauna Kea on clear days. Most rate it as doable for moderate fitness, but sun exposure and rough ground demand preparation and respect.