Oct. 16-28 marks the 55th anniversary of the Cuban Missile Crisis, a time when the United State stood on the brink of nuclear war with the Soviet Union.

Leaders of the U.S. and the Soviet Union engaged in a tense, 13-day standoff over the installation of nuclear-armed Soviet missiles in Cuba. In a TV address President Kennedy told Americans the U.S. was prepared to use military force if necessary to neutralize this perceived threat to national security.

Disaster was avoided when the U.S. agreed to Soviet leader Nikita Khrushchev’s offer to remove the Cuban missiles in exchange for the U.S. promising not to invade Cuba.

The incident was part of the "Cold War" waged between the United States and Soviet Union from 1947 to the dissolution of the Soviet Union in 1991.

It was a time of Fallout Shelters, underground bomb shelters, Civil Defense warning sirens, and emergency drills in schools.

Here's a look back at Civil Defense during the Cold War.