O'ahu's Iconic Craters
History and Hikes from Diamond Head to Koko Crater
Written by a Local Expert
Leilani AkoOʻahu's Iconic Craters: History and Hikes
Oʻahu, the "Gathering Place," hosts some of Hawaii's most recognizable volcanic landmarks. These are remnants of the Honolulu Volcanic Series. This period of rejuvenated volcanism occurred long after the island's main shield volcanoes (Koʻolau and Waiʻanae) became dormant. These younger craters offer accessible hikes and fascinating blends of geological and military history.
As of May 12, 2022, reservations are required for non-Hawaii residents for both entry and parking at Diamond Head. Reservations can be made online via the State Parks portal for $5 per person entry and $10 per vehicle parking.
Diamond Head (Lēʻahi) State Monument: Waikiki's Backdrop
The trail to Lēʻahi's summit is one of Oʻahu's most popular hikes. It's a 0.8-mile trek (one way) that gains 560 feet in elevation. The path includes switchbacks, steep stairs (including a flight of 99 steps and a spiral staircase), and a 225-foot lighted tunnel. The reward is panoramic 360-degree views encompassing Waikīkī, the southeastern Oʻahu coastline from Koko Head to Waiʻanae, and during winter months, migrating humpback whales. Allow 1.5 to 2 hours for the roundtrip hike.
Lēʻahi's strategic location led to its development as a key military fortification. The summit trail was originally built in 1908 as part of Oʻahu's coastal defense system. The Fire Control Station at the summit, completed in 1911, directed artillery fire from batteries within and around the crater. Remnants of bunkers and gun emplacements are still visible.
📚 Cultural Notes & Name Origin
Lēʻahi is the traditional Hawaiian name. The most common interpretation is "brow (lae) of the tuna (ʻahi)," as the crater's ridgeline resembles the dorsal fin of an ʻahi fish. Legend says Hiʻiaka, Pele's sister, named it during her journeys. Another translation is "fire headland," possibly referring to navigational fires lit on the summit to guide canoes.
Diamond Head got its name in the 19th century (around 1825). British sailors exploring the area found calcite crystals on the crater's slopes and nearby beach. Mistaking them for diamonds, they dubbed the landmark "Diamond Hill," which later became "Diamond Head."
Koko Crater Railway Trail: The Ultimate Stair Challenge
For those seeking physically demanding but highly rewarding hikes, the Koko Crater Railway Trail offers unforgettable challenge. This is not an official state park trail but a popular hike up remnants of an abandoned WWII-era incline railway. The "stairs" are over 1,000 railway ties (1,048 to be exact) leading straight up the side of Koko Crater, an extinct tuff cone, to its summit at 1,208 feet.
This hike is intense cardiovascular workout. The trail is approximately 1.6 miles round trip. Most fit hikers can reach the summit in 30 minutes to an hour. The descent can feel longer due to fatigue and need for careful footing. There is no shade, and it can be very hot. The summit provides spectacular 360-degree views of East Oʻahu, including Hanauma Bay, Sandy Beach, Diamond Head, and the Makapuʻu lighthouse.
💎 Diamond Head
0.8 miles one way, 560 ft elevation gain
Historic military fortification with tunnels, stairs, and panoramic coastal views. Reservations required for non-residents.
🚂 Koko Crater Railway
1.6 miles round trip, 1,048 railway ties
Intense stair workout up abandoned WWII railway. Free access with parking at Koko Head District Park. No shade or facilities.
Conquer O'ahu's Volcanic Icons
From Diamond Head's historic trails to Koko Crater's railway challenge, experience O'ahu's unique volcanic heritage.
Explore More Volcanoes💎 Diamond Head Info
- Distance: 0.8 mi one way
- Elevation Gain: 560 feet
- Duration: 1.5-2 hours
- Entry Fee: $5 per person
- Parking: $10 per vehicle
🚂 Koko Crater Info
- Distance: 1.6 mi round trip
- Railway Ties: 1,048 steps
- Summit Height: 1,208 feet
- Cost: Free
- Difficulty: Strenuous
🕐 Best Times
- Early Morning 6-8 AM
- Late Afternoon 4-6 PM
- Avoid Midday Hot & Crowded
📝 Reservations
Required for non-residents
Book via State Parks portal
No reservations needed
Free parking at District Park
🎒 What to Bring
- Plenty of water
- Sun protection & hat
- Sturdy hiking shoes
- Camera for views
- Flashlight (Diamond Head)
Fuel Your Adventure: Top Picks for Thrills and History
Oʻahu, while not currently home to active eruptions, offers volcanic landscapes transformed into arenas for adventure and sites of profound historical significance. For visitors looking to combine volcano sightseeing with other memorable experiences, the island provides unique opportunities.
Adrenaline Overload at Coral Crater Adventure Park
For those seeking an adrenaline rush in a unique volcanic setting, Coral Crater Adventure Park is a premier destination on Oʻahu. Located in a coral crater, this park offers activities designed to thrill adventurers of all levels.
Step Back in Time: Pearl Harbor Tours
While primarily known for the pivotal events of December 7, 1941, Pearl Harbor's significance as a Hawaiian landmark stretches back much further. Its traditional Hawaiian name is Wai Momi, meaning "Waters of Pearl," named for the pearl-producing oysters that once thrived in its sheltered bay.
Ziplines at Coral Crater
Six ziplines ranging from 300 to 900 feet with modern braking systems. Tandem rides available for children under 50 lbs.
ATV Adventures
Guided off-road adventures in side-by-side ATVs through rugged volcanic terrain. Drivers must be 18+ with valid license.
Historical Significance
For ancient Hawaiians, Wai Momi was protected by the shark goddess Kaʻahupāhau and served as a vital source of sustenance.
Parking is available for free at the Koko Head District Park, with a short walk to the trailhead. There are no entrance fees or reservations required for the Koko Crater Railway Trail hike.