Ever Been in a Cave When they Shut Off the Lights?

I have, but the guide told us beforehand what she was going to do.

It is amazing to think about how your eyes will never 'adjust to the light' because there IS no light!

And then there are those bats, that fly around in the cave at night with no problem, and return to the exact same spot to sleep the next day!

Oh yes, one one or two occasions. I don't think it's done in many show-caves though.

Absolute darkness - something we do not normally experience.

A lot of show-caves now limit the lighting to only that part of the passage your group is in, or to illuminate a particular feature. It's not to save electricity (though it will), but to minimise the growth of lamp-flora: algae, mosses and ferns germinating in the lamp-light, from spores carried in from outside on draughts or visitors' clothes. It used to be thought decorative but is now seen for what it is, a sort of pollution not at all natural to the surroundings.

I have been caving over the years and sometimes, if waiting somewhere underground for some reason, would turn my lamp off. I noticed this created a strange effect: if I held my hand up in front of my face it "appeared" as a shape apparently darker than the background. That is obviously impossible, and I assume what happens is that the brain "knows" the hand is there and tries to image it.

Of a sort. Picture yourself working waaaay up inside the pressure hull of a nuclear submarine where you shimmy up and in only with inches to spare on any side of you and then, some asshat down on the deckplates trips over the cord to your only light source in the form of your drop light, which plunges you in to darkness. He keeps walking of course because it's nothing to him/her.
Two things happen immediately. Your body begins to swell due to panic and secondly, you're groping in absolute blackness for your toolbag hoping you remembered to put a backup flashlight in it. There's also a third I suppose, but I'll refrain....😤

I don't think I've visited a cave with lights; the caves I explored most recently (at Pinnacles National Park) didn't have any and parts were pitch black. You just had to have a flashlight with you. It sounds fun though.

yes on more than one occasion visited caves and i could only hear drops of water forming stalagmites. we stayed in the dark for about ten minutes on one tour while the guide was talking. the mind creates its own colors in the dark.

There's a local cave that does this, but they tell everyone to get into this one chamber, and he explains what's going on, then shuts off the lights, so you know it's coming. Hate when they do that.

No, but I've been in many underground mines (with a mining engineer friend) with the headlamps turned off for a bit. Black upon black and yes a strange feeling.

I have done that. It was weird that I couldn't see my hand in front of my face. Remarkable experience!

I've never been in a cave with lights I don't think.

Yes I have been, total and complete darkness

Yes. Although it was very long ago, I'm pretty sure that happened when we visited Mammoth Cave. Kind of a strange feeling, always, being in 'total' darkness. I don't remember feeling afraid at all though, even as a child who was afraid of being alone in the dark.

Yes. Amazing feeling!

Oh yeah, Carlsbad.

Yes once never again its not a pleasant experience if your claustraphobic .

Yes, deep inside Mammoth Cave. It was a strange feeling when I opened my eyes, and there was total darkness.

Yeah. It's scary as hell, ain't it?