About 20 years ago I used to go caving once a week in the Mendip Hills, not far from where I live and poked about in a number of different caves, all of which would present some challenges to an armoured adventuring party
Birthday Squeeze in Swildon's Hole . Note the caver has had to remove the one piece of equipment he is carrying (his lamp battery) so he can get through to the next part of the cave.
(Image from Dudley Caving Club's blog)
The traverse at Eastwater Cavern, a smooth surface, but at a 40' angle ready to slide you down into a crevice
(Image from WAYA blog)
The Drainpipe in Goatchurch Cavern (wiggly)
(image from Pinterest)
Swildon's Hole sump 1. A short underwater passage, adventurers would need to hold their breath for 30 seconds
(pic from Carbis Bay Crew blog)
These are some of the more extreme passages (not the most extreme, it has to be said), and there are areas where one can walk upright, and indeed large and wonderful caverns
The Throne Room in Stoke Lane Slocker (I never did this challenging cave!)
(Image from Dudley Caving Club's blog again)
but they are all connected by tortuous narrow passageways involving crawling or wriggling, with no level floors and plenty of piles of boulders to clamber over.... which would make for an exciting (and literal) Dungeon/Cavern crawl.
The point of this rambling is that I am getting a real itch to get back underground. I chucked my kneepads and helmet away when we moved house 6 years ago, but I am getting a whispering in my head to lure me back down below...............
Entrance to Swildon's Hole
one of the fascinating things for me is that an innocuous little hole like this can lead to over 9000 metres of cave passageway, 167 metres deep.... but could you get down with plate armour and a 10' pole?