Some of the largest caves in the U.S. are national parks ... Mammoth Cave National Park in Kentucky Meramec Caverns in Missouri Natural Bridge Caverns in Texas Oregon Caves National Monument ...

Puns aside, many caves here are accessible to those ... it's worth a daytrip out to Lake of the Ozarks State Park, the largest state park in Missouri, about 90 miles northeast of downtown Springfield.

West of the Missouri River dividing the state ... Spanning at least 167 miles, Wind Cave National Park is the sixth-longest cave in the world and is home to perhaps the world's largest ...