Deepest Underground Bunker Or Complex

I was wondering what the deepest bunker or complex would be, how far down would it be? Is there a limit physically as to how far down deep into the Earth one can go? I thought it would be fun to discuss this.

reply to post by Wirral Bagpuss


I believe the worlds deepest active mine is 2.3 to 3.3 miles deep, considring the earths crust ranges from 20 to 50 miles thick, I would presume based any deeper would not be practical.

As for specifics regarding military bases, I can not be sure. However NORAD, though not deep below sea level is a good example of military infrastructure "underground"

Though Tau Tona gold mine in South Africa is the deepest mine in the world 3.9km, you can actually get closer to the center of the earth is the Kidd Creek base metal mine in Ontario, Canada (Kidd Mine) which is aprox 3000m deep. This is due to the greater equatorial radius of the earth at Tau Tona.

How deep can a mine go ?

Temperature is the biggest one. The temperature of the earth's crust increases downward at about 30°C for every kilometer of increased depth. That means a 3 kilometer deep mine might reach temnperatures of nearly 100 C (nearly the boiling point of water. Human body temperature is 37°C and so once you are deeper than a kilometer or so, the air in the tunnels must be cooled. The air cooling systems needed for deep mines are immense and very costly,

I think this is a little good information for your subject. I read that heat and air will be your biggest problems with going deeper.

What is the deepest crater? Just wondering how far down a base would need to be to be safe.

Here are some examples that I know of.

The Kimbleton Underground Research Lab, built inside the Kimbleton Lime Mine in western Virginia, sits at approximately 7,000 feet underground. Although most of the lab modules are located only 1,700 feet down.

SNOLAB in Sudbury, Ontario is an underground physics lab which is approximately 6,800 feet underground. It was built inside the former Creighton Nickel Mine.

DUSEL (Deep Underground Science And Engineering Laboratory) in Lead, South Dakota is another underground physics lab which currently exists at about 4,000 feet underground. It was built inside the former Homestake Gold Mine. There were plans to extend the lab down to 8,000 feet but I believe this fell through.

The Soudan Mine Underground Lab in Minnesota stretches down to 2,341 feet.

The WIPP (Waste Isolation Pilot Plant) used to store radioactive waste near Carlsbad, New Mexico is approximately 2,150 feet down.

Now these facilities are deep for a reason. Wherears the average high security bunker is usually not very deep at all. They range anywhere from 40 feet down to 100 feet down. Plenty of coverage to protect from harmful levels of radiation.