Nāhuku Lava Tube: Walking Through an Underground Lava Tunnel

Nāhuku Lava Tube was one of the most unique experiences we had inside Hawaiʻi Volcanoes National Park. I did not fully know what to expect going in, but it ended up being one of the more memorable stops.

The best way to describe it is this: a massive underground tunnel carved out by flowing lava.

Once you get there, you walk down a set of steep switchback steps into the opening. And when you see it, you realize how big this thing actually is. It feels less like a cave and more like a giant passageway hollowed out beneath the earth.

What to Know Before You Go

Parking is the biggest practical issue. If the lot is full, you cannot just easily turn around. You have to keep driving before you can loop back. I had to do this twice.

If your family is okay with a little extra walking, it may be smarter to park at the previous stop and walk in.

Once inside:

• it gets very dark

• a headlamp or flashlight is a must

• watch for puddles

• the ground can surprise you if you are not paying attention

Even with my headlamp, it was darker than I expected.

Final Take

This is one of those “you are not going to see this everywhere” experiences. If you are exploring the park, I would absolutely put this on the list.

Read the broader park context in our main Hawaiʻi Volcanoes National Park guide, and pair it with Puʻuloa Petroglyphs or Hōlei Sea Arch. For the whole trip, see our Big Island guide.