It had been 20+ years since I had been in Crystal Cave, not much has changed inside! It's a beautiful cave, where you can see paths of polished marble and many interesting formations. My kids and hubby who had never been really thought it was a cool thing to see. The save is about 50 degrees year round, regardless of weather above ground. If you can't take the cool, take a light jacket. The walk inside the cave is about a 1/2 miles (inside is a pretty easy walk).
Know ahead of time: It is a half mile HIKE down to the cave entrance, which means coming up back is a half mile UP. If you are in good shape, it won't phase you, just wind you a bit. If you have physical issues, take your time and take water with you on warm days. If you have small children, go at their pace, or be preparped to help carry them.
You cannot take food into the cave or anything other than water. If you have food in your car, there are bear boxes there free of charge to store you food. YES there are active bears in the area and yes they go into the parking lot.
The road getting to and from the cave is very twisty and mostly not divided. It will take you about 30 mins to go 6 miles as you can really only do about 20-25 MPH on the road. We got treated to see a bear cross the road and 3 staggs (with full set of antlers, it was cool!).
BUY your tickets ahead of time at Lodgepole of the Sequoia visitor center. You do not buy tickets at the cave, if you do you may get turned away or have to wait for a while to be let down for a cave tour.
Lastly, follow the rules. Don't be the ones who think vandalizing the cave (we had a horrible group who broke about every single rule) because you WILL get the Park Rangers called on you.
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