In 1829 Sr. Santiago Arguello received the title of property to the twenty five thousand acre "Rancho Tia Juana" from Jose Maria Encendida, the Governor of both Californias, then under Mexican rule. In 1848 the Tijuana Valley became part of the International Border when Mexico lost Alta California (Northern California) in the war with the United States. This became a key factor driving it's socioeconomic structure. Tijuana changed from a cattle pasturing area, to a customs site, to a thriving metropolis.

Urban settlement started in Tijuana (note the proper name is Tijuana, not Tiajuana as many visitors repeat) around 1889 when the heirs of Sr. Arguello and Sra. Augustin Olvera entered into an agreement to establish a basis for the development of the present city. The signing of their agreement on July 11, 1889 is considered the actual founding date of the city of Tijuana.

The future of the town as a tourism center was clear at the outset. During the last portion of the 19th century, visitors from California came to watch horse races and boxing matches, buy souvenirs, and enjoy the thermal waters.

Tijuana was also a small stage for the Mexican Revolution when revolutionaries loyal to Ricardo Magon took over the town in 1911. Shortly, thereafter, federal troops arrived and routed the rebels. San Diegans watched the battle from the safety of the international border.

The twenties changed Tijuana forever, actually it was the enactment of Prohibition in the U.S. which sent droves of Americans across the border to partake in legal drinking and gambling. Large and impressive casinos opened, like Agua Caliente in Tijuana.

International events in the 1940's had a profound effect on Tijuana. Many American tourists were attracted to Tijuana's nightlife, and the migration of Mexicans from other parts of the country increased considerably. Tijuana's population tripled in that decade, from 22,000 to 65,000 in 1950. The 50's saw a shift from the nightclub scene toward family-oriented tourism.

Currently Tijuana is again experiencing a dramatic demographic change. The present population is estimated to be between 1.8 and 2 million inhabitants, making the city the fourth largest in the country behind Mexico City, Guadalajara, and Monterrey. Tijuana is now the most crossed border in the world. Although tourism is a big part of this, Tijuana and it's surrounding area has become a major player in NAFTA with new maquiladoras and industrial plants springing up every month.