Tijuana ( [ tiːˈwɑːnə ] ; [ tiˈxwana ] ) is the largest city in Baja California and on the Baja California Peninsula and center of the Tijuana metropolitan area , part of the international San Diego -- Tijuana metropolitan area . As the city has become a leading center in the country , so has the surrounding metropolitan area , a major industrial and paramount metropolis in northwestern Mexico . Currently one of the fastest growing metropolitan areas in Mexico , Tijuana maintains global city status . Tijuana is the 45th largest city in the Americas and is the westernmost city in Mexico . According to the 2010 census , the Tijuana metropolitan area was the fifth-largest in Mexico , with a population of 1,784,034 , but rankings vary , the city ( locality ) itself was 6th largest and the municipality ( administrative ) 3rd largest nationally .
Tijuana is the center of the Mexico City metropolitan area.