December 30, 1853.<br />The treaty, known as the Gadsden Purchase, was signed in Mexico City.<br />Named after the U.S. Minister to Mexico, James Gadsden, the treaty settled the dispute over the location of the Mexican border west of El Paso, Texas.<br />For the price of $15 million — later reduced to $10 million — it established the final boundaries <br />of the southern United States.<br />30,000 square miles of what is now New Mexico and Arizona was included in the purchase.<br />The land was deemed to be a highly strategic location for the construction of the southern transcontinental railroad.<br />Eight years later, in 1861, the Southern Pacific branch of the Central Pacific Railroad was established.
