Salt mines in particular are of the safest kind in the whole world, they are super stable. It's a self supporting rock with enough plasticity that the whole thing doesn't crumble down.

If you ever have privileged info of a huge earthquake happening, going into a salt mine is probably not the worst idea.

Plus it rehabilitates your lungs to be in a salt mine for a long time.

The only earthquake that happened in the region I am living during my lifetime was caused by a collapsing salt mine, though. (Small magnitude. I only heard about it because I was working at a particle accelerator lab at the time and the machine crew observed some beam instability caused by the ground vibrations, so they talked about it.)

> Plus it rehabilitates your lungs to be in a salt mine for a long time.

It what?

Like victorian doctors prescribed sea air for healing. When it didn't work they prescribed country air.

These treatments work best in conjunction with sunlight, which is unfortunately lacking in salt mines.

Not a terrible idea really: Victorian times were also when the industrial revolution was happening, and unregulated coal plants and factories were belching out unimaginable amounts of pollution into city air. Getting away from that mess and breathing clean air probably was good for you if you had health problems.

The joke is they send people someplace else, and when it doesn't work they send them back. Guessing most city dwellers could not afford a doctor or resting up on the countryside or beach.

Halotherapy / speleotherapy, pseudo science. Not harmful but probably just placebo

https://en.wikipedia.org/wiki/Halotherapy

https://en.wikipedia.org/wiki/Speleotherapy

The comparison I'd make is between a small section of an inactive salt mine with some people in it, and a "modern" city from a century or two ago.

The damp (salt is hydrophilic) walls of the mine could, over time, act as pretty effective passive filters for microscopic particles in the air.

Meanwhile, the city's air is just loaded with particles from all the coal/wood/etc. being burned as fuel.

I mean clean air is definitely good for you and a salt mine is probably cleaner than a city

I believe it's a disservice to science to say something doesn't work when there's not enough data yet. I know of a few cases of mines with many people swearing by them and the research I've read said "inconclusive, needs more research", not that "it doesn't work". There's meta studies available: https://pmc.ncbi.nlm.nih.gov/articles/PMC6435215/

There’s a reason the saying goes “back to the salt mines.” It’s just a generally pleasant place that people love to be in.

Salt mines are safe as long as you are careful to keep water and salt separated. If people operating a mine (or maintaining a closed one) are negligent or incompetent or under-invest into maintenance bad thinks can happen, especially in a wet climate - water will dissolve salt and not only in/around the mine itself but in underground salt layers connected to the mine which can span tens of kilometers away from the mine.

Salt mines are generally pretty stable because if they weren't stable they would be full of water and and not worth the effort to try and mine.

It could be a potential problem in some areas but salt domes are so numerous that nobody really bothers with less-than-ideal ones for mining.