San Diego and Tijuana used to be one region that was cut in half by the Mexican-American war of 1846. https://en.wikipedia.org/wiki/Conquest_of_California http

San Diego and Tijuana used to be one region that was cut in half by the Mexican-American war of 1846. https://en.wikipedia.org/wiki/Conquest_of_California https://en.wikipedia.org/wiki/Conquest_of_California https://en.wikipedia.org/wiki/San_Diego–Tijuana https://en.wikipedia.org/wiki/San_Diego–Tijuana