There was a science fiction TV show from the 1960’s called the Time Tunnel in which a massive U.S. government agency was building a time machine, called the Time Tunnel. The show itself was basically the adventures of two scientists who go back in time to prominent historic events and occasionally forward into the future.
But the best part of the show was the underground base in which the Time Tunnel was located. 36,000 people worked in the giant underground base in Arizona. Entering the base was done by going through a Batcave like entrance and then driving into a colossal parkade. The ground above the base looked like regular desert. The corridors and walkways in the base crisscrossed over thousand foot high drops.
This must be one of the best underground bases ever conceived.
Project Tic-Toc is a top secret U.S. government effort to build an experimental time machine, known as “The Time Tunnel” due to its appearance as a cylindrical hallway. The base for Project Tic-Toc is a huge, hidden underground complex in Arizona, 800 floors deep and employing over 36,000 people. The directors of the project are Dr. Douglas Phillips (Robert Colbert), Dr. Anthony Newman (James Darren), and Lt. General Heywood Kirk (Whit Bissell). The specialists assisting them are Dr. Raymond Swain (John Zaremba), a foremost expert in electronics, and Dr. Ann MacGregor (Lee Meriwether), an electro-biologist supervising the unit that determines how much force and heat a time traveler is able to withstand. The series is set in 1968, two years into the future of the actual broadcast season, 1966-67.