Big Hole

A winding, blood-red tunnel of hardened lava navigable by foot.

This geothermal hot spring hides beneath a slowly growing mineral dome.

Massive crater in central Oregon.

This color-changing crater lake in El Salvador is occasionally impenetrable to sunlight.

An unusual double cinder cone with a bent oval crater, in the Lunar Crater Volcanic Field.

This volcanic crater lake is renowned for its perfectly round shape, stunning blue-green waters, and unique geological properties.

Millions of years of erosion created the feature for which this rock formation is aptly named.

Legend says that Wade the Giant scooped up a handful of earth to throw at his wife, leaving behind this round valley.