Thirty years ago I spent three months as a USGS intern as part of a team taking depth readings on explored portions of caves.
What makes Mammoth so cool is the huge size of the passages. But, I don't think I'd have been nearly as impressed if I'd not spend three months mostly crawling through the tiny passageways that comprise the vast majority of most caves.
Wyandott cave once ran a 12 hour 2 person + 2 guide tour into the tighter areas. If they're still running that tour then I highly recommend it. At the time, it was damned near impossible to ever see a cave in that way unless you had a friend already hooked into the spelunking community.
I went to The Caves of Han and had a blast, and also went to some smaller natural caves. We have some divers in the family and I was well aware about the dangers and difficulties of exploring caves(systems) like this. Walking around on pathways with railings, lights and every comfort you need for walking through a cave, it sometimes felt surreal or weirdly conflicting.
I did some guided underwater caving myself in coastal reefs in Egypt. There was a point where you had turn up from horizontal, slightly left, and about 45degrees back upward where you came from, with only the light you make with the divers light. This tunnel was just large enough to fit you with divers equipment, so basically a human sized hamstertube. and even though our guide was fantastic and dive prep was 10/10, that was intense.
Cave exploring is super cool and very very dangerous and risky and unpractical, so it's not hard to feel great awe when you see some caves like this 'conquered', knowing the effort it must have taken :-) .
I did some guided underwater caving myself in coastal reefs in Egypt.
I've been in tight caves, skydived and may soon buy an ultralight, climb without a rope (class 3ish) with fatal fall exposure, etc. I've managed to stay alive because of heavy risk assessment and mitigation efforts.
Cave diving is a whole different category of risk. I'd never attempt it. As a hobby it's certain death. Please say something about this in your post above.
so it’s not hard to feel great awe when you see some caves like this ‘conquered’, knowing the effort it must have taken :-)
Mammoth Cave isn't "conquered" -- not by a long shot! They explored eight more miles of it for the first time just three years ago (and have apparently added six more without making the news since then, since the total is now 426), and estimate there may be another 600 miles yet unexplored.
The first recommended video when I searched for them was this one. Very cool, and confirmed for me that even though I don't have claustrophobia, cave diving is definitely not for me.
What they don't always touch on is how long they are in those caves for. They will be in the caves for 5+ hours, with a couple hours where one guy is solo and squeezing through areas with no hope of rescue if he gets stuck.
I am certain one of them is going to die in a cave after he went off alone and was crushed as he crawls under a breaking off flake or drowns when he gets turned around underwater. They don't have any sort of gas detectors either and have ignored serious signs that they are not in an area with breathable air.