From time to time ICBM missiles are randomly removed from their silos and sent to Vandenberg AFB, California, for a test launch.  The purpose is to ensure that those missiles will indeed launch in a real world emergency if required to do so.   Below photos show a Minuteman II ICBM being removed from its silo at Whiteman AFB, Missouri, most likely for a test launch at Vandenberg (Whiteman is no longer a missile base, but instead is home for the Air Force's B2 stealth bomber, Spirit.)

Missile transporter-erector used to remove/replace missiles and to transport them.

Personnel entrance to underground missile silo.

Attachment point for transporter-erector hydraulic jacks.

Base of hydraulic jacks in place.

Silo cover being opened with hydraulic equipment.  The cover is about three feet thick of reinforced concrete
and is designed to survive anything other than a direct hit by a nuclear weapon.  In an actual launch powerful
explosives would hurl the 100 ton plus cover along its tracks and away from the silo.

Transporter-erector in process of being raised to a ninety degree angle.

Transporter-erector is hinged at rear to allow cargo portion to tip upwards.

Cover being removed as transporter-erector elevates over silo.                Transporter-erector fully in place over silo.

Transporter-erector lift mechanism.                                                           Missile to be removed (warhead previously removed).

Worker attaching lift mechanism to missile.

Note safety harness attached to worker.  It's a long drop to the bottom of the silo (about 80 feet).

Lift mechanism in place.                                                                         Missile being lifted into the transporter-erector.

Missile fully into transporter-erector and locked in place.

Cab of transporter-erector.

Cargo portion of transporter-erector being lowered.                                 Bottom of empty missile silo.