The Chamizal dispute was a border conflict over about 600 acres (2.4 km2) on the U.S.-Mexico border between El Paso, Texas, and Ciudad Juárez, Chihuahua. It was caused by a shift in the Rio Grande, as a survey presented in 1852 marked differences between the bed of the Rio Grande (in Spanish: Río Bravo del Norte) and the present channel of the river. The Chamizal was once the only link between El Paso and Ciudad Juárez and tensions over the territory during the historic Taft-Diaz summit almost resulted in the attempted assassination of both presidents on October 16, 1909.