It is 16 miles. To avoid speeding, allow 30-minutes, door to door. Park in the lower parking lot at Mitchell Caverns. The upper lot is tiny and rarely has an open space. No big trucks in the upper lot... not enough room. If you do not have reservations, don't bother, unless you just want to see the view.
Just about 15 minutes.
Less than 10 mim or so drive.
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