Kazumura Cave

Kazumura Cave is a lava tube and has been surveyed at 40.7 miles (65.5 kilometers) long and 3,614 feet (1, 102 meters) deep, making it the longest and deepest lava tube in the world. The cave is located on the island of Hawaiʻi on the eastern slope of Kīlauea. Kīlauea is the most recently active volcano on the Big Island. The ʻAilāʻau lava flow that contains Kazumura Cave originated from the Kīlauea Iki Crater about 500 years ago.

Cave data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).