12 Otherworldly Volcanic Landscapes: From Lava Tubes to Steaming Calderas

11. Manjanggul Cave, Jeju Island, South Korea: Journey Through a Lava Artery

Jeju Island, a volcanic wonderland, hosts one of the finest lava tube systems in the world, with Manjanggul Cave being a publicly accessible highlight. This UNESCO World Heritage site stretches for kilometers, though only a portion is open. Walking through its vast, tunnel-like passages, some reaching 30 meters high, reveals remarkable volcanic formations: lava stalactites, lava benches lining the walls, and the world's largest known lava column. It’s an ingenious natural subway system, carved by ancient rivers of fire, offering a cool, subterranean exploration of volcanic plumbing.