The
international border between Mexico and the United States runs from
San Diego,
California, and
Tijuana,
Baja California, in the west to
Matamoros,
Tamaulipas, and
Brownsville,
Texas, in the east. It traverses a variety of terrains, ranging from major urban areas to inhospitable deserts. From the
Gulf of Mexico it follows the course of the
Rio Grande (Río Bravo del Norte) to the border crossing at
El Paso,
Texas, and
Ciudad Juárez,
Chihuahua; westward from that binational
conurbation it crosses vast tracts of the
Sonoran and
Chihuahuan Desert, the
Colorado River Delta, westward to the binational conurbation of
San Diego and
Tijuana before reaching the
Pacific Ocean.
The border's total length is 3,169 km (1,969 miles), according to figures given by the International Boundary and Water Commission.[1] It is the most frequently crossed international border in the world, with about 250 million legal crossings every year.[2]
The nearly 2000 mile (3,138 km or 1,950 miles) international border follows the middle of the Rio Grande — according to the 1848 Treaty of Guadalupe Hidalgo between the two nations, "along the deepest channel" — from its mouth on the Gulf of Mexico a distance of 2,019 km (1,254 miles) to a point just upstream of El Paso, and Ciudad Juárez. It then follows an alignment westward overland and marked by monuments a distance of 858 km (533 miles) to the Colorado River, during which it reaches its highest elevation at the intersection with the Continental Divide. Thence it follows the middle of that river northward a distance of 124 miles (38 km), and then it again follows an alignment westward overland and marked by monuments a distance of 226 km (141 miles) to the Pacific Ocean.
The region along the boundary is characterised by deserts, rugged mountains, abundant sunshine and by two major rivers — the Colorado and the Rio Grande (Río Bravo del Norte) — which provide life-giving waters to the largely arid but fertile lands along the rivers in both countries.
