Volcanic Wonders Around The World You Never Knew Existed

19. Askja – Iceland’s Remote Martian Caldera

Deep in Iceland’s central highlands, Askja is a remote volcanic system that resembles an alien landscape more than an earthly destination. Its massive caldera houses Lake Öskjuvatn, one of the deepest lakes in Iceland, as well as the warm, milky-blue Viti crater—popular for adventurous bathing. Surrounded by black lava fields, steaming vents, and snow-dusted ridges, Askja offers one of the most surreal volcanic landscapes on the planet. It's no wonder NASA trained Apollo astronauts here in preparation for the moon.