About 45 minutes from our Big Island bed and breakfast, a concrete staircase descends into the earth where molten lava once rushed toward Hilo. Kaumana Caves isn’t on most visitor itineraries. There are no tour guides, no entrance fees, and no carefully lit pathways. What you get instead is the chance to walk through ancient tunnels carved by a Mauna Loa eruption. Here’s what to know before you go.
How the Kaumana Caves Formed
In 1881, Mauna Loa erupted, sending a river of molten lava down its slopes toward Hilo. The flow threatened the town, and residents watched with growing alarm as the lava advanced. Princess Ruth Keʻelikōlani, a high-ranking aliʻi, traveled to the flow’s edge and performed traditional chants to Pele, asking the goddess to spare Hilo. Within days, the flow stopped just short of the town, a story still shared today as part of local history and cultural tradition.
While the lava cooled on the surface, molten rock beneath continued flowing, eventually draining away and leaving hollow tubes behind, now known as the Kaūmana Caves. These tubes extend for miles underground, though only a portion is accessible to visitors. Walking through them means tracing the actual path of lava from that 1881 eruption, moving from a lush tropical landscape into a dark, otherworldly environment shaped entirely by volcanic activity.
What to Expect at Kaumana Caves
When you arrive, there’s a small park area with restrooms and a picnic table just before the cave entrance. A steep concrete staircase leads down to a large cathedral-like opening overgrown with dense greenery.
As you descend the stairs, the cave splits. To the left is a smaller section (make sure you duck down as you enter this section. It’s lower than it seems). To the right is the main cave that extends about two miles and requires more crawling and rock scrambling. Most visitors explore the right section, where you can walk much farther into the tube, but both offer a unique experience.
No matter which side you choose, know that sunlight doesn’t penetrate beyond the first hundred feet or so, and it gets dark fast. The cave stays damp year-round from Hilo’s rain, and the floor can be muddy depending on recent weather.
Look up as you walk deeper, and you’ll notice roots hanging from the ceiling. These belong to plants growing on the surface above the tube. From certain angles, they have a fluorescent glow, likely from bioluminescent fungi growing on them.
The lava formations tell their own story. You’ll see drip formations where molten rock hung briefly before cooling, flow marks along the walls showing the direction the lava moved, and color variations ranging from deep black to rust red where minerals oxidized over time. In some sections, the walls look almost glazed, shiny from the heat that once passed through.
Getting There and What to Bring
Getting There and What to BringKaumana Caves State Park sits (1492 Kaumana Dr, Hilo, HI 96720) about three miles west of downtown Hilo on Kaumana Drive (Highway 200).
From Volcano Village Lodge, take Highway 11 toward Hilo, then follow Kaumana Drive uphill. The drive takes 45 to 50 minutes and offers views of Hilo and the coastline as you climb.
Parking is limited and located across the road from the cave entrance, so use caution when crossing.
What to bring:
- A reliable headlamp or flashlight is essential. Phone flashlights work in a pinch but aren’t ideal, as you’ll want both hands free for balance. Headlamps are better. Bring extras if you have them, and fresh batteries.
- Sturdy closed-toe shoes with good traction are another requirement. The cave floor is uneven and often wet. Hiking boots or trail runners work well. Avoid sandals or flip-flops entirely.
- Long pants protect your legs from scraping against rocks when you crouch or navigate tight spots. They also help if you end up sitting or kneeling.
- A light jacket or long-sleeve shirt keeps you comfortable as the temperature drops inside the caves. It’s noticeably cooler underground than in the parking lot.
- Bring water even though you’re not hiking long distances. Exploring caves is surprisingly physical, especially if you venture far into the uphill section.
Safety Considerations
Kaumana Caves require more caution than typical Big Island attractions. This is not a developed cave system with guided tours and safety measures. You’re responsible for your own well-being.
The floor is slippery. Moisture from Hilo’s rains seeps through the rock, creating algae and wet surfaces. Move deliberately. Test your footing. Use your hands for balance when needed.
Watch for low ceilings and jutting rocks. The tube’s dimensions change constantly. What was plenty of headroom a moment ago might drop to four feet high around the next bend.
Stay together if you’re exploring as a group. The caves can feel disorienting in the dark, and it’s easy to lose track of companions if you’re not paying attention.
Know your limits. If you’re uncomfortable with dark, enclosed spaces, stick to the entrance area or the shorter downhill section. There’s no shame in turning back. The uphill section gets progressively more challenging the farther you go, and you can always stop whenever it feels right.
Don’t touch or disturb anything. The cave ecosystem is delicate, and the formations took thousands of years to develop.
FAQ
How long does it take to explore Kaumana Caves? Most people spend about 30 minutes exploring the caves. You could spend less if you just want to see the entrance, or much longer if you’re exploring the far reaches of the right section.
Is it difficult? The first few hundred feet are relatively easy with good footing and reasonable ceiling height. The farther you go, the more challenging it gets. You’ll encounter lower ceilings, wetter conditions, and rougher terrain.
Is it a good place to bring kids? Kids are welcome, but with the uneven terrain and slippery surfaces, it’s better suited for older kids.
Is there a fee to enter Kaumana Caves? No! Kaūmana Caves is completely free.
Making a Full Day: Pairing Kaumana Caves with Hilo Exploration
One of the advantages of staying at Volcano Village Lodge is the flexibility of your morning routine. Your breakfast is delivered straight to your in-room refrigerator the night before, so you can enjoy it whenever you wake up, then head out to Kaumana Caves when you’re ready.
After exploring the caves, which typically takes an hour to two hours, depending on how far you venture, Hilo offers plenty of ways to continue your day.
Rainbow Falls sits just a few minutes from Kaumana Caves. This 80-foot waterfall is one of Hilo’s most photographed spots, especially in morning light when rainbows often appear in the mist. There’s a short paved path to the viewpoint, making it an easy stop after your cave adventure.
Downtown Hilo provides a complete contrast to the darkness of the caves. Browse shops along Kamehameha Avenue, grab lunch at one of the best restaurants in Hilo, or visit the Pacific Tsunami Museum to learn about the waves that shaped Hilo’s history.
The Hilo Farmers Market operates daily (biggest on Wednesdays and Saturdays) and makes a great lunch stop. Pick up fresh tropical fruit, locally made foods, and handcrafted items while sampling Big Island flavors.
Liliʻuokalani Gardens, a Japanese-style garden on Hilo Bay, is one of our favorite botanical gardens in Hawaii. The manicured grounds, koi ponds, and bay views provide a serene contrast to the raw geology of the caves.
Big Island Candies in Hilo welcomes visitors to watch cookies being made and sample their famous shortbread. It’s a sweet way to end your Hilo day trip before driving back to Volcano Village.
Plan Your Visit to Kaumana Caves
Plan Your Visit to Kaumana CavesIn a state full of natural wonders, Kaumana Caves offers something increasingly rare: an unmediated encounter with geology. While you can walk through a lava tube like Nāhuku (Thurston Lava Tube) in Hawaiʻi Volcanoes National Park, Kaumana Caves offers a more rugged, unaltered version of that experience.
For visitors staying at Volcano Village Lodge, Kaumana Caves adds another dimension to understanding how lava shapes this island. You’ve seen where lava flows on the surface at Hawaii Volcanoes National Park. At Kaumana Caves, you see where it flowed beneath the surface, leaving behind passages that feel like walking through the island’s circulatory system.
Pack your headlamp, lace up your hiking boots, and spend a morning exploring one of the Big Island’s most authentic adventures. Book your stay at Volcano Village Lodge and discover what lies beneath the surface of this remarkable island.