Spooky, wonderous, stalactite-y: Crystal Cave in Sequoia National Park returns this summer season for guided tours after a four-year closure due to consecutive natural disasters in the national park.

Crystal Cave in Sequoia National Park is reopening for guided tours after a four-year closure due to natural disasters. The cave, formed in 200 million-year-old marble, features unique geological ...

The basic tour through Carlsbad Cavern is the Big Room Route, a 1.25-mile, self-guided underground stroll around the ...