Longest lava cave
- Who
- Kazumura Cave
- What
- 65.5 kilometre(s)
- Where
- United States
- When
- 04 April 2019
The longest (and also the deepest) lava cave, an open tube down the inside of a lava flow, is Kazumura Cave, on Hawaii, USA. It is 65.5 kilometres (40.7 miles) long and descends 1,101.5 metres (3,614 feet) down the eastern flank of Kilauea volcano.