rocky texture

About Louisville Mega Cavern: Interesting Facts

  • The cavern was mined from the early 1930's to the early 1970's.
  • The mine goes under all 10 lanes of the Watterson Expressway (I-264).
  • The portion of the mine under I-264 was quarried before the highway was built in the early 1930's.
  • The Mega Cavern is approximately 100 acres.
  • Mega Cavern is classified by the Metro Louisville Government and the State of Kentucky as a building. As a matter of fact, it is the largest building in the State of Kentucky and has been given its own building code.
  • It took 12 years to receive an underground building permit.
  • The ground above and the underground below have separate zoning classifications. It is the only dual zoning area in Kentucky.
  • The underground is privately owned.
  • When you see a rock pillar, you are only seeing the top portion, which is approximately 25 to 30 feet tall. This is because the pillar was once about 85 to 90 feet tall before being backfilled with dirt and rock in order to create roads and warehouse space.
  • If you filled the Mega Cavern with boats, it could hold up to 16,000 units.
  • You cannot receive TV or radio signals in the underground.
  • There are 16 undergrounds with businesses in the Kansas City area.
  • There are 4 entrances/exits to the Mega Cavern; all together at the front.
  • The lowest entrance to the Mega Cavern is 25 feet above the top of the flood wall.
  • The underground is the largest recycling center in Kentucky by tonnage. It handles more material by tonnage than all others combined.
  • The average temperature in the Mega Cavern is 58 degrees year round.
  • Mega Cavern has two seasons; wet in the summer and dry in the winter.
  • The average temperature for this part of the world over thousands of years is 58 degrees, which is the same as the cavern.
  • Each warehouse has the heater units inside of the building. Outside warehouses have the units outside of the building.
  • A 10 ton heater dehumidifies a 50,000 square foot building.
  • Utility costs are 75%-85% cheaper than the cost of a building not underground.
  • Most of the roads and warehouses in the underground have motion sensors that control the lights to conserve energy.
  • All buildings and road sprinklers have water in them and they will not freeze in the winter.
  • One building (warehouse unit) had a dance with 800 people and workers.
  • Air circulates through by natural air pressure, trying to equal the outside, similar to a stove pipe on a wood stove.
  • Supplemental fans are used to keep down the fog that can be created.
  • The #1 entrance to the cavern had an 8 inch snow fall one day when it was not snowing anywhere else in the city.  This was due to moist air escaping from the cavern while hitting the below freezing temperatures outside the cavern......forming perfect conditions for a snowfall.
  • The walls of the underground buildings are made of sheets of Fiber-rock.
  • Walls of the buildings are hanging on a metal frame hanging from the roof.
  • Each wall of the building has a 2 hour fire rating.
  • A green building is a building built with energy savings incorporated into its construction.
  • The underground has radiant heat from rock, heavy insulation, motion detector lights, and recycles the heat from the lights and machines, as well as human bodies in the cavern. All of these items help it to be a green building.
  • Over 850,000 truck loads of backfill have been delivered so far to raise the floor up to the level that it is at today.
  • Each warehouse HVAC unit has an ultraviolet light to kill air born mold, mildew, and bacteria.
  • Approximately 70% of the Louisville Zoo is located above the cavern.
  • The limestone in this area is part of the Cincinnati Arch.

Let Your Underground Adventure Begin Today!

Louisville Mega Cavern
1841 Taylor Ave,
Louisville, KY 40213
(877) 614-6342 
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