San Diego–Tijuana

San Diego–Tijuana is an international transborder agglomeration, straddling the border of the adjacent North American coastal cities of San Diego, California, United States and Tijuana, Baja California, Mexico. The 2012 population of the region was 4,922,723, making it the largest bi-national conurbation shared between the United States and Mexico, the second-largest shared between the US and another country. In its entirety, the region consists of San Diego County in the United States and the municipalities of Tijuana, Rosarito Beach, and Tecate in Mexico. It is the third most populous region in the California–Baja California region, smaller only than the metropolitan areas of Greater Los Angeles and the San Francisco Bay Area.

The largest centers of the urban area maintain global city status and as a whole the metropolitan region is host to 13 consulates from Asian, European, North American, Oceanian, and South American nations. Over fifty million people cross the border each year between Tijuana and San Diego, giving the region the busiest land-border crossing in the world. Since the implementation of the North American Free Trade Agreement in 1994, San Diego–Tijuana has become a dominant commercial center in the United States and Mexico. The economic success of globalization has allowed San Diego–Tijuana to grow to the third richest region in the former Californias region, with a GDP of $136.3 billion in 2002. Renowned for natural beauty, tourism is a leading industry in the region and its coastal environs have been paramount factors in the growth of action sports-lifestyle companies. Other key industries include military, biotech, and manufacturing.

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