Thurston Lava Tube (Nāhuku)

Nāhuku, usually called Thurston Lava Tube, is the easily reached lava tube in Hawaiʻi Volcanoes National Park, and it was named for the Thurston family. That name carries the park's own history: Lorrin A. Thurston, grandson of the American missionary Asa Thurston, was one of the driving forces behind establishing the park, having invested in the Volcano House hotel from 1891 to 1904 and then used his ownership of The Honolulu Advertiser to push the idea that William R. Castle had first proposed in 1903.

The developed section is lit and walkable. Beyond it an undeveloped stretch runs a further 1,100 feet before dead-ending into the hillside, and that part is closed to the public.

The tube's recent history is a reminder of what it sits inside. The 2018 Kīlauea eruption produced some 60,000 recorded earthquakes, and they left large rockfalls and new cracks in the tube. It was closed, and reopened on 21 February 2020 only after the rockfalls were cleared, sensors were installed to monitor the cracks, and the drainage and parking were rebuilt.

The wider setting explains why. Kīlauea is one of the most active volcanoes on Earth, and the park is a working volcanic landscape rather than a preserved one. In 1790 a party of warriors, along with women and children in the area, were caught in an unusually violent eruption; many were killed, and others left footprints in the lava that are still visible today.

The first western visitors came in 1823, the missionary William Ellis and Asa Thurston. Ellis wrote of the sight: a spectacle sublime and even appalling, and that they stopped and trembled.

The tube is lit from 8 a.m. to 8 p.m.; bring a flashlight if you visit outside those hours. To protect the site, the park asks visitors to avoid touching the walls or the tree roots. If the lot is full, the Kīlauea Iki Overlook parking is about half a mile away. The tube was once hung with hundreds of lava drippings, which is why the park asks you not to touch the walls or the tree roots.