 Tijuana is the 45th largest city in the Americas and is the westernmost city in Mexico.According to the 2015 census, the Tijuana metropolitan area was the fifth-largest in Mexico, with a population of 1,840,710, but rankings vary, the city (locality) itself was 6th largest and the municipality (administrative) 3rd largest nationally.The international metropolitan region was estimated at about 5,158,459 in 2016, making it the third-largest metropolitan area in the former Californias region, 19th largest metropolitan area in the Americas, and the largest bi-national conurbation that is shared between US and Mexico.