Tijuana and Nogales are two Mexican border cities located on the United States-Mexico border. Tijuana is located in the northwestern part of Mexico, just south of San Diego, California. It is the most populous city in the Mexican state of Baja California and is known for its vibrant nightlife and cultural attractions. Nogales is located in the northern part of Mexico, just south of Tucson, Arizona. It is a major commercial center for the region and is known for its large number of maquiladoras, or factories that produce goods for export. Both cities are important gateways for trade between the United States and Mexico.