We didn't venture into Yellowstone National Park. We went last year and while each of us had been there several times before, it was fun because we took the kids. Instead, we decided to drive deeper into Montana and visit the Lewis and Clark Caverns. We arrived midday and got there just in time to use the restroom, visit the gift shop and head out on the tour. There was a short hike that was about a 1/2 mile up to the cave with a 300 foot rise in elevation. (I won't lie, it was a little difficult for me. I'll blame it on the growth in my belly.)
As we looked down off the trail we could see the muddy Jefferson River by which Lewis and Clark travelled twice without discovering the caverns. (In fact, the caverns were discovered about 60 years later by a hunter named Dan Morrison. Lewis and Clark "lend" their names to the caverns for the tourist draw.)
I have never seen anything like the formations in the caverns. They were amazing. (I kept my eyes out for Fraggles, but saw none...they must be shy.) Everywhere we turned there was another natural formation that varied greatly from the formation only a foot away. Stalactites hung from the ceiling, stalagmites jutted from below. Sometimes they met to form columns. There was flow rock and "popcorn" and smooth limestone, glistening in the dim light. The tour guide described the way they form...something about water and calcite and other things I didn't commit to memory because I was in awe of what stood before me. But I can tell you this...it was dang cool!
There were several "rooms" in the caverns and several tight spaces including a fun, wet little beaver slide. My favorite room was the fantasy room. Up until that point everything had looked brown/yellow/grey. Once inside the rooms with the ultraviolet lights the spectrum of colors was amazing. Shades of pink, red, purple, and orange lent to the fantastical feel of the rock formations. I'm not that great with descriptions so here are some pictures to do the talking for me.