7 Things You Need To Know Before Visiting Diamond Head On Oahu, Hawaii

One of the most recognized landmarks in Hawaii, Diamond Head State Monument in downtown Honolulu is my own personal Everest — one that I successfully summited! Climbing to the top of Diamond Head’s crater rim is a popular activity for visitors as well as a favorite workout loop for locals. It’s not every day that you can boast that you’re hiking up the side of a volcano in a capital city, but it happens every day here.

Diamond Head is part of the system of cones, vents, and eruption flows of the Honolulu Volcanic Series. Thankfully, there’s no chance of an eruption these days! But the long-dormant crater and crater walls offer visitors spectacular views and one of the state’s most rewarding hikes.

The curious name, Diamond Head, was given to the area by 19th-century British soldiers who thought the nearby sparkling calcite crystals were much more precious. But indigenous Hawaiians call the landmark Leahi, from lae for “ridge” and ahi for “tuna.” If you use your imagination, you can see how the crater rim resembles a tuna’s dorsal fin.

Today, Diamond Head is protected as part of the Diamond Head State Monument. Encompassing approximately 475 acres, it is one of the largest green zones in an American state capital.

1. Arrive By Foot, Car, Or Public Transit

If you’re feeling ambitious, it’s entirely possible to hike to the gates of Diamond Head State Monument from Waikiki. Depending on where you start, it could take up to an hour — and then you still have to explore the park! But more people do it than you might think, especially fitness-oriented locals.

Most visitors, however, prefer to save their energy for the hike to the top of Diamond Head, and there are several ways to get to the park using other forms of transportation. For instance, the Waikiki Trolley blue line includes a stop at the gates of Diamond Head State Monument. However, it only makes financial sense to purchase a trolley pass if you plan to ride the trolley to other attractions.

The more frugal option is to take the city bus, which costs around $3 for adults. Bus number 23 from Kuhio Avenue (toward Diamond Head) is the most direct route via public transportation. While you’ll likely spot the State Monument sign, let the driver know where you’re headed to be on the safe side. Tickets are usually good for 2 hours, so if you’re a speedy hiker and a frugal traveler, hold on to your transfer stub, and your return trip might just be free.

Of course, you can always drive (there is ample parking) or catch a taxi or Uber. Diamond Head State Monument isn’t very far from the Honolulu Zoo, the Waikiki Aquarium, and Diamond Head Beach Park. If you’re planning to visit these attractions during your trip to Oahu, it makes sense to do so after your Diamond Head visit, when you’re still in the neighborhood.

2. Reservations Are Essential 

Diamond Head State Monument is open every day of the year, including holidays, from 6 a.m. to 6 p.m. The latest you can enter the park to hike is 4:00 p.m. since the round trip takes between 90 minutes and 2 hours. On peak days, the park welcomes more than 3,000 people. As such, as of May 12, 2022, all out-of-state visitors must have an advanced reservation to enter Diamond Head State Monument.

Reservations can be made up to 14 days in advance for now, but the long-term plan is to change the system so reservations can be made up to 30 days in advance. Visitors are asked to arrive within 30 minutes of their reservation time. However, you must leave by the end of your reservation time. So if you are a slow stroller, make sure you’re there at the beginning of your time slot!

3. Best Time To Hike: Mornings

If you’re visiting Hawaii from mainland North America and jet lag has you awake bright and early, visit the park before the crowds get there. We started our hike not long after the park opened, and I’m so glad we did. The temperatures were relatively cool, there weren’t many people (though we were far from alone), and it was neat to see so many locals getting their workouts in. It helped me realize that Diamond Head is so much more than a tourist attraction — it’s a beloved part of the community.

4. Pay Online — But Bring Cash

Prior to the new reservation system, admission to Diamond Head State Monument was $5 per car (no matter how many people were in it) and $1 for pedestrians, and it was cash only. But the new system changes everything! Now the reservation system means you pay $5 per person in advance online, via credit card. You can also pay the $10 parking fee if you wish to park. If you have ID that proves you’re a Hawaiian resident, your entry and parking costs are free.

I highly recommend bringing along some extra money to buy some refreshing shave ice after your hike. There’s usually a food truck selling it in the parking lot and, in my opinion, it’s the best way to treat yourself after your adventure.

5. Minimal Gear Needed

In addition to a bit of money, you should bring your own water bottles (there are fountains at the beginning of the trail, but none as you ascend), a hat and sunscreen, and good walking shoes. I have to say, I did see quite a few people wearing casual flip-flops, and they were undeterred by the loose gravel. To each their own, but I’m glad I had my sneakers!

6. Expect Stairs And Gravel

The trail to the summit was built in 1908 as part of Oahu’s coastal defense system. The hike itself is only 0.8 miles each way, but you gain 560 feet in height along the way. The trail includes a concrete walkway, loose gravel and soil, a 225-foot-long tunnel (it looks pitch black as you approach it, but it is dimly lit inside), and many, many stairs. In addition to the loose gravel, there are several narrow and awkward parts of the trail, and your ankles will appreciate the extra support that tennis shoes provide.

Having not realized there were so many stairs involved — I assumed I’d be hiking up a slope, not steps — I have to admit I was worried that Diamond Head would defeat me! The stairs themselves weren’t impossibly difficult, but they were harder on me because I hadn’t expected them. Now that I know what to expect, I don’t find the route nearly so intimidating. The hike to the top of Diamond Head is a workout, for sure, but it’s manageable. A little pre-trip planning goes a long way.

7. Great Views And Incredible History

Without a doubt, the most spectacular thing you’ll see at Diamond Head State Monument is the incredible view. Locals like to say that on a clear day, there’s nowhere else on Earth where you can see so far overland. Based on my very unscientific observations, I concur! At the top of Diamond Head, all of Honolulu opens up to you. For early risers, I can’t imagine a more breathtaking place to enjoy the sunrise.

However, the land views pale in comparison to the ocean views. From crashing, deep navy blue waves to delicate shades of turquoise lapping at the shore, this is the Hawaii of your dreams — nothing but sun, sky, and surf. In the winter season, you might just see humpback whales frolicking in the distance. And at the base of Diamond Head, you’ll notice a jaunty white lighthouse. A facility of the United States Coast Guard, the lighthouse was built in 1917 and added to the National Register of Historic Places in 1980. If you think it looks familiar, that’s because it was featured on a postal stamp in 2007! Unfortunately, you can’t visit it, so you’ll have to enjoy the views you get from Diamond Head.

While I expected incredible views — and I was not disappointed — I noticed something else that I found equally intriguing. There are many objects along the way that point to the crater’s history as a military observation point. The land around Diamond Head Trail was part of a military base for decades, and artillery cannons, cement bunkers, and an observation deck were built on the crater. You can still see the remnants of Diamond Head’s past life as you complete your hike. With an odd mix of curiosity and sadness, I observed chunks of concrete and wire slowly disintegrating and rusting on the ground. How long will it be until Diamond Head swallows up its own history entirely?

If you’re interested in learning more about the fascinating history behind Diamond Head, you can visit the park’s interpretive kiosk. The staff members are extremely knowledgeable and are always eager to answer questions.

Rest assured that the trip down Diamond Head is faster and easier than the trip up, but you should still exercise caution around the steep areas and keep your eyes open for congested spots filled with tourists wielding rogue selfie sticks!

Planning a trip to Oahu? Check out the best things to do there, plus Honolulu’s best free and frugal activities. And be sure to make time for Pearl Harbor and the North Shore.