Diamond Head State Monument, Hawaii

Diamond Head State Monument is a 475-acre section of land southeast of Honolulu, Hawaii. It is known for its volcanic crater, historic hiking trail, military history, and coastal views. The crater was formed over 300,000 years ago. The trail to the summit was built in 1908. It was initially made as part of O'ahu's coastal defense system but was turned into a hiking trail many years later. The hike is just under a mile from the trailhead to the summit, but if you hike from outside the park into the interior, you reach a round-trip hike of about 3 miles. The area is beautiful, the hike is short but steep, and the views are incredible.

Challenges

No Pets are allowed in the park, except service animals.
If you are not a Hawaii resident, then entry reservations are required. Parking reservations are also available but are harder to come by. The last entrance to hike the trail is at 4:00 pm, and the gates lock at 6:00 pm. Reservations should be made as soon as possible because spots are limited and sell out fast.
- Entry
  *CREDIT CARD ONLY*
  Hawaii Residents = Free w/Hawaii ID or DL
  Non-Hawaii Residents = $5
  Children 3 and under = Free
  Non-Commercial Vehicles
  Resident = No Charge with ID
  Non-Resident = $10 Per Vehicle
  Commercial vehicles fees
  1-7 Passenger Vehicles = $25
  8-25 Passenger Vehicles = $50
  26+ Passenger Vehicles = $90
  (NON-RESIDENT RESERVATIONS REQUIRED)

Reservations

The hike to the summit is NOT ADA accessible. The trail is often uneven and rough, and the last 0.1 miles is comprised almost entirely of stairs.
The hike covers less than a mile from the trailhead to the summit, but in that short distance you will climb 560 of elevation.
It is crowded. Even arriving first thing in the morning, we had to stop a few times before the line started moving again. As the day goes on the line, the number of stops, and the durations of each stop will increase.

Equipment

Sunscreen
Water
Snack
Good hiking shoes or boots

The Approach

This one can be tricky. If you were able to secure a reservation for parking along with your entry reservation, then you can drive right into the main parking area during your reservation time and find a parking spot. A secondary option is the overflow Diamond Head Tunnel Parking area that can fit 12 vehicles. These 12 spaces are also available for those without parking reservations.

If you cannot get a parking reservation, your options become a little more limited. I would recommend getting entry reservations for the 6 am slot. This will mean waking up early, but you will avoid most of the crowds, and you are more likely to get one of those 12 parking spots just before the tunnel. If those 12 spots are filled, a couple more options are still available.

Our Experience

We chose the 6 am reservation and arrived at the monument at 5:30 am. A line of cars was already extending from the tunnel entrance nearly to the Diamond Head Rd intersection. We were unsure if any of the 12 tunnel parking spots would be available once we could reach the location. Rather than wait in line and hope, we elected for plan B. We turned around and drove east on Diamond Head Rd to a small parking area (21.264762, -157.797485). We got our gear, walked along the paved trail back to the road leading to the monument, and hiked up the road, through the tunnel, and into the monument area.

The Trail

The trailhead begins at the Diamond Head Visitor Center. The first half of your hike will be slightly uphill through the crater’s floor. We moved through this section quickly, passing many people along the way. Even at 6 am, this place was already bustling.

Soon, we reached the much more vertical section of the hike. An uneven, unpaved, and rugged trail would carry us nearly to the summit. The trail is narrow, with only a few good places to pause to rest. I imagine this is exacerbated when you have people going up and down. There was barely room to pass slower groups, and often, there was no room to try. The few times we were forced to pause were due to others ahead of us needing to rest in one of these narrow corridors along the trail.

Nearing the summit, you will reach the tunnel. This was the slowest section of the trail, and we paused several times before we could finally get through to the other side. This bottleneck is caused by the narrowness of the tunnel, the bifurcation of the trail on the other side, and the chaos of people going in different directions at that intersection.

The Summit

On the other side of the tunnel, we had two options. To the right was a tall staircase leading up into the mountainside. To the left, we remained outside with a paved path and views. We chose to go left. The views were great from every angle along this pathway. You could look down into the crater or over the rim along the coastline.

Following the stairs up leads to the summit and the bunker monument. When we reached this location, we realized the right option from the tunnel’s exit led to this location from inside the bunker. This location is the “Instagram Spot.” Everyone is looking for a place to take a selfie where the view is beautiful, but no one else is getting in the shot. It is a challenge to get both.

Inside the bunker, shorter folks will be far more comfortable than taller folks. We took in the view from inside and imagined taking a military post here to watch for enemy ships and aircraft. From this point, we could have taken the interior path down the stairs to the tunnel, but we wanted to take in the views a little more. We returned to the exterior and took in the views a little longer before starting our return trip down into the crater.

The Return Trip

The return trip is where we made stops along the wider sections of the trail to take in the views. It was easier to go down than up since the overlooks were on the side of the trail as the traffic was downward, and fewer people were going down than up. Even with the stops, going down was faster, and we were soon back on the paved trail, walking briskly through the flatter portion of the crater.

The grassy section looked very similar to African plains, and for a moment, I thought about the lions in The Ghost and the Darkness film. Those scenes could have easily been shot in this location. At the visitor center, we looked through the small assortment of shirts, hoodies, magnets, and patches.

When we were ready, we made our way through the main tunnel, down the road, along the park path, and returned to our car. We enjoyed the shade, breeze, and time to dry out a bit. We also had a chuckle at the numerous chickens that were living in the tree near our car.

Summary

Diamond Head is just one of those things you need to experience when visiting O’ahu. It is a beautiful, fun, and memorable experience. Be sure to plan accordingly so you have your parking and entry reservation at best and your entry reservation at the minimum. Be patient, especially if you cannot go first thing in the morning. We were so glad we could fit this hike into our trip. We recommend anyone visiting O’ahu enjoy this for themselves.