Nogales is a divided city on the Arizona-Sonora border. The Spanish-language name "Nogales" refers to walnuts, as walnut trees once grew here.

Split by a wall which runs down the middle of International Street between the United States of America and the United Mexican States, the title "Heroica Nogales" was conferred on the Mexican portion of the city in recognition of the Battle of Ambos Nogales of August 27, 1918.

International Street was once a wide main street much like any other. In 1918, American authorities opened fire on a Mexican civilian attempting to return to Sonora, igniting an international gun battle which raged for days with reinforcements brought in on both sides. The battle ended with the construction of the first permanent border fence, which split the village in two.

See:

• Nogales (Sonora)
• Nogales (Arizona)