Tratado de Tlatelolco

The Treaty of Tlatelolco, signed in Mexico City in 1967, prohibits nuclear weapons in Latin America and the Caribbean, making the region the world’s first nuclear-weapon-free zone in a densely populated area. Mexican diplomat Alfonso García Robles championed the treaty and won the Nobel Peace Prize in 1982 for this work.

Do not confuse the treaty with the Tlatelolco massacre of October 2, 1968, when the army fired on student protesters in the same Mexico City square: two very different events tied to the same place name.