In October 1962, the U.S. discovered that the Soviet Union was secretly constructing nuclear missile bases in Cuba, just over 90 miles from Florida. This led to a 13-day standoff known as the Cuban Missile Crisis. President Kennedy instituted a blockade around Cuba and demanded the Soviets remove the missiles. After tense negotiations, the Soviets agreed to dismantle the Cuban missile bases in exchange for the U.S. promising not to invade Cuba and agreeing to remove its own missiles from Turkey. The crisis ended, but it brought the world dangerously close to nuclear war.