Last updated: October 26, 2024
Place
Boundary Monument One
NPS Photo (Image modified using artificial intelligence)
Quick Facts
Significance:
Boundary Monument One marks the beginning of the overland boundary between the United States and Mexico from El Paso west to San Diego.
MANAGED BY:
International Boundary and Water Commission (IBWC)
Boundary Monument 1 was erected in 1855 by the Emory-Salazar surveyors. The Emory-Salazar expedition was an international delegation consisting of representatives from Mexico and the United States tasked with setting the physical boundary for over 2000 miles between the two countries. The Treaty of Guadalupe Hidalgo ended hostilities between the United States and Mexico and seceded over 336 Million acres to the United States, including parts of present day New Mexico, Arizona, Colorado, California, Nevada, and Utah. From Paso del Norte (Present Day El Paso and Ciudad Juarez) to the east, the border would follow the Rio Grande River to the Gulf of Mexico. Initially, the boundary to the west would follow the course of the Gila River, although the Gadsden Purchase not long after required an overland boundary set by surveyors.
Setting fixed points in El Paso and San Diego and working towards the middle, the survey crews worked together to determine the nearly 2,000 mile overland boundary. Boundary Monument 1 was erected on the international boundary to mark its beginning point in El Paso. The monument not only marks the boundary between the United States and Mexico; it also marks the point where Texas, New Mexico, and the Mexican state of Chihuahua meet.
Boundary Monument 1 is open to the public during most business hours. In 2020 a private non-profit organization installed a section of border wall in close proximity to Boundary Monument 1, which partially restricts public access to the monument. The National Park Service does not manage access to Boundary Monument 1 and is not able to provide precise information regarding when the monument is open.