The Titan I missile was a liquid fuelled two stage ICBM deployed by the
United States between 1962 and 1965 (See image of missile below).
It was the first US nuclear-warhead missile to be deployed in hardened
underground silos.
Each Titan I site could launch three missiles from three separate silos.
The silos, fuel stores, tracking radars, control center and power dome were
housed in vast subterranean complexes with hundreds of yards of
interconnecting tunnels. (See artist's image below).
They were the largest and most complex missile installations ever built.
One can assume that in terms of excavation and construction costs today
that they would cost hundreds of millions of dollars to build.
Ehren Hotchkiss is a young woman who spent part of her childhood
growing up at a decommissioned Titan I missile base that her father
had bought from the USAF.
She has a 4-part blog entitled "My Missile Base Story" on YouTube.
In Part 4, she and a cameraman takes us on a 26 minute tour of the
underground complex.
Particularly impressive is the opening segment where we are taken
down several flights of stairs to the complex level, the segment starting
at 6:25 were we are taken through one of the tunnels, the segment starting
at 15:22 showing inside one of the three missile silos and the segment
starting at 17:16 where we are taken into the power dome, which originally
housed its own power-plant capable of delivering a megawatt.
Video Here -
https://www.youtube.com/watch?v=19J8FSIM4nE
The video provides an insight into how the Cold War arm's race spared
no expense in the construction of ICBM missile silos. In themselves,
the Titan I missiles and bases were impressive pieces of engineering
but that feat tends to belie the horrific scenario if the rockets ever
had to be used against target sites.
Titan missiles were eventually obsoleted by solid-fuelled missiles such
as the Minuteman series.
Today, the United States still has some 450 Minuteman-III ICBM's in
hardened silos on hot standby, deployed in Wyoming, North Dakota
and Montana.