What event marked the beginning of the cuban missle crisis the united states refused to remove its nuclear missiles from cuba the u. s spy planes photographed soviet nuclear missles in cuba cuban revolutionaries staged a coup against fidel castro soviet spy planes photographed u. s nuclear missiles being built in cuba

The event that marked the beginning of the Cuban Missle Crisis was that  U.S spy planes photographed Soviet nuclear missles in Cuba.

The Missile Crisis in Cuba is the name given to the conflict between the United States, the Soviet Union and Cuba in October 1962, generated as a result of the discovery by the United States of Soviet bases of medium-range nuclear missiles in Cuban territory.

It was one of the biggest crises, together with the Berlin Blockade and the Able Archer 83 exercises, between both powers during the Cold War and in Cuba, where nuclear war was closest. In fact, only twice in history has a DEFCON 2 defense condition been reached in the United States.

The crisis covers the period between the discovery of the medium-range ballistic missile R-12 and R-14 of the Soviet Union (October 15, 1962) until the announcement of its dismantling and transfer back to the Soviet Union (October 28, 1962).