Diamond Head

Diamond Head State Monument in Honolulu takes in the inside and the outer slopes of the crater, which formed in an explosive eruption. The summit trail was built as part of Oʻahu's coastal defense system, and it climbs from the parking lot on the crater floor to the Fire Control Station on the summit. If you do not live in Hawaiʻi, you need an entry reservation, plus a parking reservation if you drive in, made on the State Parks Diamond Head reservation site. Busy times of day can sell out, so book early, and arrive early in your reservation window, because late arrivals may be refused entry or parking. Anyone without a reservation is turned away, except local residents with a valid Hawaiʻi State ID. Hawaiʻi residents enter free with a Hawaiʻi driver's license or state ID, but friends and family visiting with them are not exempt and must buy entry in advance. Entry fees are paid by credit card, not cash. The hike is steep and strenuous. It starts on a paved walkway, then turns uneven and steep, climbs steep stairs and passes through a lighted tunnel into the Fire Control Station, and the last stretch is all stairs. That station once directed artillery fire from batteries in Waikiki and Fort Ruger. At the summit are bunkers and a navigational lighthouse, and the view runs along the shoreline from Koko Head to Waiʻanae, with passing humpback whales possible in winter. Wear good walking shoes, bring water, and wear a hat and sunscreen. Stay on the trail, where falling rocks are a listed hazard and smoking is not allowed. No pets are allowed in the park except service animals. The facilities on the crater floor are accessible to visitors with disabilities, but the summit trail is not ADA accessible. Everyone must be back out through the tunnel to the outside of the crater by closing time, when the Department of Defense secures the park.