Gadsden Purchase
The Gadsden Purchase was a area of land sold by Mexico to the United States in 1854. It is now part of Arizona and New Mexico, south of the Gila River and west of the Rio Grande. Its size was . The United States paid Mexico 10,000,000 dollars, which is worth 230,000,000 dollars in 2019 money. This trade was officially called the Treaty of Mesilla.