The Cuban Missile Crisis was arguably the most dangerous conflict of the Cold War. This incident between the United States and Soviet Union almost lead to all out nuclear warfare. This was a result of the United States putting missiles in Turkey and the Soviet Union putting missiles in Cuba.
Over 13 days in October of 1962, President John F. Kennedy and Nikita Khrushchev constantly deliberated over an agreement on how to end this without warfare. The US agreed not to invade Cuba again and the Soviet Union agreed to remove their missiles in Cuba. The US would later remove their missiles from Turkey as well.