Diamond Head

Diamond Head is Oahu's famous volcanic tuff cone above Waikiki, with a reservation-required summit trail, crater views, old military features and sweeping Honolulu scenery.

Diamond Head, Oahu

Diamond Head is one of the most famous landmarks on Oahu and the entire state of Hawaii. It has once been an active volcano, but hasn't spewed any ashes for more than 150,000 years. The extinct crater and lookout point at the peak of it is a popular hiking destination for many. In fact, Diamond Head is one of the most photographed and painted spots on Oahu, adorning many wall calendars and postcards.

Located at the eastern end of Waikiki and right on the ocean, Diamond Head has already made an impression to early sailors. In 1825, British sailors noticed small sparkling calcite crystals in the beach sand nearby the crater and named the mountain Diamond Hill. This name was later changed to Diamond Head. This is how the crater got its English name.

The Hawaiian name for Diamond Head is Le'ahi, a contraction of lae, meaning point of land and 'ahi, meaning yellowfin tuna. So Le'ahi means “point (of the) ahi fish.” From a distance, the mountain looks like the dorsal fin of the ahi fish, hence its Hawaiian name Le'ahi.

Diamond Head was purchased by the federal government in 1904 for $3,300. In the 1930s, a couple of gun emplacements for coast artillery defenses were built. After the attack on Pearl Harbor in 1941, further gun emplacements, pillboxes and foxholes were built on Diamond Head to be able to better defend Oahu in the future. Many of them still remain on the crater rim and one underground facility, the Birkheimer Tunnel, houses the headquarters for the State Civil Defense Agency. Today, the entire mountain and crater is a state park known as Diamond Head State Monument.

Diamond Head Crater measures 3,520 feet (1,073 m) across and 760 feet (232 m) in height. A hiking trail leads from the crater up to a lookout point. But be prepared to climb some stairs. In fact, there are two stairs, one has 99 steps and a second one has 76 steps. There's also a 225-foot (69 m) hardly lit tunnel through which you'll have to go. The tunnel is a remnant of the former military use of the crater. So you should be in good physical condition to do the hike. But it's definitely worth the effort once you reach the top, after about 30-40 minutes if you're in good shape. The view is spectacular, especially on a clear and sunny day.

Bring some water and sunscreen because it will get hot. In case you forget, there is a comfort station at the base of the otherwise undeveloped crater, where you can buy water (water fountains and restrooms are also there, as is a truck that sells hot dogs and hamburgers).

Key Features

Iconic volcanic tuff cone above Waikiki
Hawaiian name Leahi
Part of Diamond Head State Monument
Non-resident entry reservations required
Parking reservations required for non-resident vehicles
Normal hours are 6:00 am to 6:00 pm daily
Last entry is 4:30 pm for the 4:00 pm reservation
Summit trail includes stairs, tunnels and exposed sections
Historic military lookout features along the route
Wide views of Waikiki, Honolulu and Oahu's south shore

Frequently Asked Questions

Why is Diamond Head also called Leahi?

Leahi is the Hawaiian name often translated as brow of the tuna, a reference to the crater's profile as seen from certain angles.

How did Diamond Head get its English name?

Early Western sailors mistook calcite crystals in the crater for diamonds, which led to the name Diamond Head.

What makes the crater different from many Oahu mountains?

Diamond Head is a tuff cone formed by explosive volcanic activity, so its broad crater and steep outer rim look different from the older Koolau range behind Honolulu.

Why are there military features along the trail?

The summit route passes old coastal-defense features from the early 1900s, when the crater was used as part of Oahu's military lookout and defense system.

What can you see from the summit?

Clear days bring views over Waikiki, Kapiolani Park, the south shore, downtown Honolulu, offshore surf breaks and the ridges behind the city.