Diamond Head Trail
✓ Verified against the agency · NPSShort but steep trail to the summit of Lēʻahi (Diamond Head), the iconic tuff cone on O'ahu's south shore. 0.8-mile climb through a tunnel and up steep stairs inside the old military fortification (Fort Ruger, 1910). Panoramic views of Waikīkī, Honolulu, and the Ko'olau Range from the summit. Reservation required ($5/person). One of the most visited trails in Hawaii — over 3,000 hikers per day.
Safety classification
Open year-round, 6:00 am-6:00 pm daily (last trail reservation 4:00 pm, last entry 4:30 pm, gates locked at 6:00 pm - you must be out); closed Christmas and New Year's Day. The risk window is midday heat on the shadeless crater slope - go early morning. Status 2026-08-23: reopened Sat 8/22 after the Hurricane Lala / Tropical Storm Moke closure (DLNR notice 8/21/26).
- ▲Heat and full sun exposure - DLNR terrain rating is 'Hot, Dry, Slopes' with no shade; carry water, hat, sunscreen
- ▲Steep, uneven natural tuff surface after the first 0.2 mi of pavement - DLNR: 'requiring caution and appropriate footwear'
- ▲Steep stairways near the summit (the last 0.1 mi is all stairs) and a narrow 225 ft tunnel
- ▲Lockout: gates close at 6:00 pm sharp
0.8 mi one-way, 560 ft gain; DLNR's hiking page rates it 'Moderate' (~2 hr round trip) while the park page calls the ascent 'steep and strenuous' - classified day-hike, not walk, on the steeper reading. Heavily managed: 3,000+ visitors/day, ranger presence, concrete walkway, lighted tunnel. Out-of-state visitors MUST book entry and parking reservations in advance (gostateparks.hawaii.gov, required since May 2022, $5/person + $10/vehicle, credit card only); Hawaii residents free with ID, no reservation. Not ADA accessible above the crater floor. No pets.