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Sequoia & Kings Canyon National Parks Vacation Ideas
"(2:19 in the video) A visit to Crystal Cave is a must-do in your travel plans. Discover the mysterious underground world of Sequoia National Park when you venture down through the twisting network of dark caves. On your guided tour, pass through the spiderweb-like gate of Crystal Cave and venture further to explore some of the more than 200 marble caverns spanning the cave system."