Tasmans Arch, Tasmania, Australia

© Gary Bell/Minden Picture

An arch that rocks. Tasmans Arch, Tasmania, Australia

Ready for a coastal adventure? Welcome to Tasman National Park in Tasmania, an island state of Australia about 150 miles off its southeastern coast. Spanning more than 41 square miles, this park features dramatic cliffs and distinctive columns of dolerite rock. Tasmans Arch, seen in today's image, is a standout example. Shaped over time by the Tasman Sea, it was once the roof of a massive sea cave. The sea's pressure, combined with air, sand, and stones, slowly pried open the vertical cracks in the cliff, dislodging chunks of rock. The cave kept growing, deepening, and lengthening, until it eventually gave way, leaving behind this towering natural bridge. Tasmans Arch is named after the Dutch explorer Abel Tasman, who also lends his name to the state of Tasmania.