Honolulu reservations: Diamond Head, Hanauma Bay, Pearl Harbor

Three of the best-known sights on Oʻahu now need planning before you arrive. Diamond Head requires a reservation for non-residents, Hanauma Bay uses online reservations and closes two days a week, and the USS Arizona Memorial at Pearl Harbor is free but works best with a reservation.

It belongs with the Honolulu travel guide and the wider Hawaii planning guide, and it supports where to stay in Honolulu. Fees and rules here were read from the official pages on 1 October 2026. They change, so open each page again the week you travel.

Diamond Head State Monument is the volcanic crater at the eastern end of Waikīkī, and the summit trail is one of the most popular short hikes in Hawaii. It is about 1.6 miles round trip with a steady climb, stairs and a tunnel, and it ends at a viewpoint over the city and the coast.

The official page is the Diamond Head State Monument page, which links the reservation system. The page does not state how far ahead slots open, so check the booking site. Children 3 and under are free, and Hawaii residents enter free with valid ID.

Book the earliest slot you can, because the climb is hot and exposed by midday. Bring water, sun protection and shoes with grip, and avoid the trail if the weather is stormy. If you cannot get a slot, the Kāhala and Diamond Head side of town is still a pleasant place for a coastal walk, and you can see the crater from the Waikīkī beach.

Hanauma Bay Nature Preserve is a sheltered bay with coral reef and clear water, and it is one of the easiest places on the island to snorkel. It is run by the City and County of Honolulu as a protected preserve, which is why it has fixed hours, an education video and limits on visitors.

The official source is the Hanauma Bay Nature Preserve site, where reservations open about two days ahead. Slots go quickly on weekends and holidays, so be ready when they are released, and keep a fallback beach in mind.

Plan the visit for the morning, when the water is calmer and the light is best for snorkeling. Use reef-safe sunscreen, or wear a rash guard instead, and do not touch or stand on the coral. If you do not own gear, rent it on site or from a shop in Waikīkī. A visit takes about two to three hours including the video.

Pearl Harbor National Memorial includes the USS Arizona Memorial, the visitor center and nearby museums. The National Park Service runs the memorial program, which includes a short film and a boat ride to the memorial itself. The program is free, but booking a time slot is strongly recommended.

See the National Park Service Pearl Harbor page for the current program schedule and ticket details. Arrive early, especially if you hold reserved tickets, and leave bags at your hotel, since paid storage near the entrance adds a queue. The last boat departs at 3:30pm, so do not plan a late afternoon visit.

Other Pearl Harbor sites, such as the battleship and aviation museums, are separate attractions with their own tickets and prices. Check each site's official page before you plan, because they are not covered by the free memorial program.

The three have different rhythms. Diamond Head is a fixed-time hike where the reservation matters most, Hanauma Bay is a half-day swim with a hard closing time, and Pearl Harbor is a longer morning with queues and security. Fees apply to non-residents and were read from the official pages on 1 October 2026; Hawaii residents pay less or nothing at some sites, so do not rely on a local's price.

Costs add up beyond the fees. Parking at Diamond Head and Hanauma Bay is a separate charge, and a rental car for a single day often costs more than two rideshares. If you stay in Waikīkī, a rideshare to each sight is usually the simplest choice, and TheBus works if you have time. For longer plans, see getting around the USA and decide where a car truly saves money.

Group the three sights by area and time of day. Diamond Head and Hanauma Bay are both on the east side of Honolulu, so you can pair a sunrise hike with a late-morning snorkel on a day when the preserve is open. Pearl Harbor is west of downtown, so give it its own morning and an easy afternoon.

A workable three-day sequence is Pearl Harbor on the first morning, when you are still adjusting to the time difference; Diamond Head and an easy beach afternoon the next day; and Hanauma Bay on a Wednesday to Sunday. Remember that Hanauma Bay is closed on Mondays and Tuesdays, and that reservations for it open two days ahead, so book it once you know the weather.

If you also plan other islands, check their rules early. Haleakalā on Maui has a sunrise reservation system, and Hāʻena State Park on Kauaʻi requires non-residents to book entry or parking in advance. Our guides to Haleakalā and Hanalei cover those.

Weather in Honolulu changes quickly, and a closed trail or a rough sea can undo a plan that depends on a single slot. Keep a flexible morning and a backup for each sight. If Diamond Head is too wet or slippery, a coastal walk along the Waikīkī promenade or the Kāhala shore gives views without the climb. If Hanauma Bay is closed or full, snorkel at a calmer beach on the south shore with lifeguards, and check the surf report first.

If Pearl Harbor tickets are gone, arrive early for standby, since the memorial offers limited standby places each day, and use the visitor center's exhibits while you wait. The first program starts at 8am, and the last boat leaves at 3:30pm, so a late start leaves little room.

For every sight, read the official page again the week you travel. Closures for maintenance, security or weather are posted there first. Fees and hours change too, and the pages above are the source of truth, not this guide. If a rule differs from what you read here, follow the official page.

Pack light. Pearl Harbor does not allow bags, so carry only a wallet, phone and ID, and leave the rest at your hotel. At Diamond Head, bring water, a hat, sun protection and shoes with grip, because parts of the trail are steep and exposed. At Hanauma Bay, bring a swimsuit, a rash guard or reef-safe sunscreen, a towel and a waterproof pouch for valuables.

Carry a printed or saved copy of each reservation, and a photo ID. Keep your phone charged, since the reservation sites and the park pages often need a signal. An eSIM gives you data on arrival, so you can pull up the booking at the gate rather than searching for Wi-Fi.

You do not need a tour for any of these three sights. Rideshare and TheBus reach them, and the reservations are simple to book yourself. A guided tour makes sense if you do not want to arrange transport, if you want a guide for the history at Pearl Harbor, or if you prefer one booking for several stops. It does not replace the reservation rules, so check whether the price you are quoted includes entry, parking and any fees.

Before you travel, make sure your ESTA is approved if your passport needs one, and compare travel insurance for medical cover and trip delays. Set up an eSIM so you can show reservations on your phone, and browse tours and tickets for other Oʻahu bookings.