The elevator car was very small, and we were packed in, nose-to-buttcheek, since I was quite small myself at the time. Oy. It was only closed at the bottom -- it was shaped like a hot air balloon basket, with the upper sides open. We kids were strictly admonished to not even try to touch the sides of the shaft as they went by, though I don't think I could reach that far up anyway.
Our ears popped several times on the way down. The ride to the bottom took over a minute, which seemed very long for an elevator not stopping at any other floors!
The ride down was dark, which gave our eyes time to adapt. Once we reached the bottom, the mine seemed bright, although the light level was probably quite low in absolute terms. I remember the light fixtures being attached to the ceiling, drilled straight into the salty rock.
There were vehicles down there! This blew my mind, and even at the young age, I recognized them as older style vehicles, Jeeps and such which had been down there for years. I have no idea how they were kept from rusting immediately. The air tasted of salt. Everything was covered in salt dust.
We were given a ride on a vehicle of some sort, I don't remember if we were in the back of a Jeep or on a trailer hayride-style, but we covered quite some distance into the mine. The room-and-pillar system was pointed out, and we got to see the conveyor bringing salt from the active face being mined at the moment, though we didn't get close to the active room itself.
They let us grab some lumps of salt to bring them home. Whatever you could fit in a backpack to ride the elevator back up, is what I was told. Some of those samples made it into my rock collection, some are still in my memory-box. I don't know what became of the others, but I was using one as a paperweight in elementary school.
I don't know why they closed the mine to tours, but it's a great loss to education. Obviously experiences like that are transformative to a young kid!
In the years since, I've oft wondered if the exceptional stability of that geological formation might make it good for other sorts of uses. Archive storage, or perhaps it's the "secret undisclosed location" where important people scuttle off to when bad things happen.
The size of the mine, several miles and with extents under four cities, is remarkable. It's surely expanded further since this map was made:
http://www-personal.umich.edu/~copyrght/image/solstice/sum99...