"A dramatic lava tube within Hawai‘i Volcanoes National Park that illustrates how molten flows carve subterranean tunnels; visitors often expect glowing lava but instead explore a cooled tunnel formed centuries ago, with the reminder that active flows can reach temperatures up to about 2,000°F. The site is a common starting point for nearby hikes and provides an easy, tangible lesson in volcanic geology." - Flora Stubbs Flora Stubbs Flora Stubbs is the executive editor of Travel + Leisure. She has been a journalist for over 20 years, and a travel editor for over a decade. Travel + Leisure Editorial Guidelines