We invited some family members to go as well and they also were so glad they came along.
So first go to this site to purchase tickets: Purchase Cave Tour Tickets You can do it at the visitors center, but they often are sold out especially if you have a larger group like we did. If you just want 1 or 2 you may be able to get some same day, but you never know.
After that you hike about a mile and half up to the cave entrance. Its is pretty steep and I would recommend lots of water. There is no where along the trail to get any, so don't be stingy. There is 20 markers along the way to help you know how far you have left or have gone. So at 10 you are half way there. Along the way there is beautiful views, facts about the rocks and some steep spots.
Inside is always cold. It will always be a constant 45 degrees. So I suggest bringing a sweater or jacket. If you have kids make sure they have some kind of jacket as well, cause it is cool. The tour can take an hour to an hour and a half. So it may feel nice at first but no one else on the tour wants to hear whiny kids the whole way, so come prepared.