In 1846 the Mexican–American War began and the United States continued to expand its borders under the doctrine of Manifest Destiny. As the war came to California, the Battle of San Pasqual was fought in the northern areas of modern-day San Diego. In 1848 the war ended with the Fall of Mexico City and boundaries were redrawn which created a border between San Diego and Tijuana, south of San Diego Bay. 1919 saw the implementation of Prohibition and the rapid growth of Tijuana tourism. Americans flocked to the city, which had become a major destination for the Hollywood elite, which led to the construction of the Agua Caliente Tourist Complex which in turn spurred the rise of hotels and overall growth in the city.