Missile silo

A missile launch facility, also known as an underground missile silo, launch facility (LF), or nuclear silo, is a vertical cylindrical structure constructed underground, for the storage and launching of intercontinental ballistic missiles (ICBMs).

The structures typically have the missile some distance below ground, protected by a large "blast door" on top. They are usually connected, physically and/or electronically, to a missile launch control center.

Until the 1960s ICBMs had been launched from surface bases. The Soviet Union used completely above-ground launchers similar to those found at a spaceport. In many cases they were the same ones used for civilian launches, such as Site 1 and Site 31. They were vulnerable to bomber attacks by the United States.

The La Coupole facility is the earliest known precursor to modern underground missile silos still in existence. It was built by the forces of Nazi Germany in northern Occupied France, between 1943 and 1944, to serve as a launch base for V-2 rockets. The facility was designed with an immense concrete dome to store a large stockpile of V-2s, warheads and fuel, and was intended to launch V-2s on an industrial scale. Dozens of missiles a day were to be fuelled, prepared and rolled just outdoors of the facility's concrete casing, launched from either of two outdoor launch pads in rapid sequence against London and southern England. A similar-purpose but less-developed facility, the Blockhaus d'Eperlecques had also been built, some 14.4 kilometers (8.9 miles) north-northwest of La Coupole, and closer to both facilities' intended targets for V-2 rocket bombardment meant for launch from both of them, towards southeastern England.

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