Funny that these are the very first two replies. It seems like you’re either a cave person who would react "wow, what a fascinating geological formation’ or a non-cave person, who would react "eh, it’s just a hole in the ground’. I know, without having seem Mammoth Cave myself, that I am a cave person. If you look into your heart you should find the answer.
Indeed. That ceiling smarts!
Yeah, my cousin’s wife is similar. After a visit to the Grand Canyon, her impression was “it’s just a big hole in the ground”. 
Wow. I’m guessing if she visited Niagara Falls she would say, “eh, it’s just a vertical river.” Just can’t impress some people 
Honestly, I wasn’t too impressed by the Grand Canyon, either. It’s just too big: You can’t really take it all in. There’s a big cliff here, and then way over there, there’s another cliff.
Now, Yellowstone Canyon, there’s an impressive canyon.
Grand Ole Opry is not downtown , they moved to a new place in the suburbs in the 70s. Building is still downtown and they have other concerts there. It started out as a church.
and now Nashville is big for bachlorette parties. Not just parties for locals, people fly in from all over for those. My son’s GF went to one there last fall.
Yeah that is what I heard. I’ve been to Carlsbad and it was spectacular. Mammoth is much bigger but not nearly as aesthetically pleasing.
Depends on how you define “bigger”. Though both of them are, by any reasonable metric, Really Big Caves.
Mammoth means really big.
I was remembering from the last time I was at Carlsbad which was about a decade ago. The rangers were basically saying Mammoth is bigger but ours are better. A quick look online search shows Carlsbad is 30 miles long. Mammoth is directly connected with what was originally thought of as separate cave systems and is 420 miles long. Its the longest in the world. Carlsbad has what is apparently the largest single chamber by volume in the US.
Even more than that, I’d suggest it reflects your level of curiosity WRT natural phenomena. How far would you drive to see WHATEVER natural phenomena?
For example, I had long thought of visiting a national forest about 6 hrs away. Visited a few years ago. Was kinda unimpressed - but nevertheless glad I visited and was able to form my own opinion. In the other direction, there are some old growth trees maybe 6-7 hrs from me. Definitely on my short list. Tho I could imagine many people saying they are “just trees.” When in Hawaii, we went to South Point, just to be able to say I had been in the farthest S point of the US.
In my life’s travels, there are few stops I regret having made, but several instances in which I FAILED to stop because it was out of my way and required a side trip, I was on a schedule, whatever.
We went to Luray Caverns in WVA. It’s an interesting place.
Read about an older guy who went to Grand Canyon park but somehow never actually saw the canyon. He was not impressed.
BTW Luray Caverns is in Virginia not WV
Lost World Caverns in Lewisville is pretty neat. The tour there is self-guided so you can wander around and linger as long as you want. The day I went I was the only one in the cave and had the place to myself for almost an hour. Lost World Caverns is supposedly the home of the Bat Boy, but they don’t play that aspect of the place up other than a few Weekly World News covers on the wall.
It’s a hole in the ground. For those of us with claustrophobia, not a place to visit.
Similarly, IIRC, Mammoth Cave has extensive ground above grounds. We never stayed for an extended period, but it could be a nice destination outside/above the cave.
Smoke Hole Cavern and Seneca Cavern are the most popular tourist caves in WV,or were back when I lived there, and they’re well worth seeing. My family visited Seneca Cavern when I was a little kid and I was fascinated and thrilled; there are a couple of things I still remember vividly. Also the Seneca Rocks are nearby, and they are spectacular. Luray Caverns, near the Natural Bridge in VA (not all that far from WV) is pretty visual too. So you’ve got a variety of interesting, close-by, guided cave experiences to choose from.