The concept of a route from one tip of the Americas to the other was originally proposed at the First Pan-American Conference in 1889 as a railroad;
however, nothing ever came of this proposal.
The idea of the Pan-American Highway emerged at the Fifth International Conference of American States in 1923,
where it was originally conceived as a single route.
The first Pan-American highway conference convened October 5, 1925 in Buenos Aires.
Mexico was the first Latin American country to complete its portion of the highway, in 1950.
No road in the U.S. or Canada has been officially designated as the Pan-American Highway, and thus the primary road officially starts at the U.S.-Mexico border.
The original route began at the border at Nuevo Laredo, Tamaulipas (opposite Laredo, Texas) and went south through Mexico City.
Later branches were built to the border at Nogales, Sonora (Nogales, Arizona), Ciudad Juárez, Chihuahua (El Paso, Texas), Piedras Negras, Coahuila (Eagle Pass, Texas), Reynosa, Tamaulipas (Pharr, Texas), and Matamoros, Tamaulipas (Brownsville, Texas).
On the other hand, several roads in the U.S. were locally named after the Pan-American Highway.
When the section of Interstate 35 in San Antonio, Texas was built, it was named the Pan Am Expressway, as an extension of the original route from Laredo.
Interstate 25 in Albuquerque, New Mexico has been named the Pan-American Freeway, as an extension of the route to El Paso.
U.S. Route 85, which goes north from El Paso, is designated the CanAm Highway, which continues into Canada in the province of Saskatchewan, before terminating at La Ronge.
The CANAMEX Corridor is also similarly designated throughout the western United States, and continuing into the Canadian province of Alberta.
The original route to Laredo travels up Mexican Federal Highway 85 from Mexico City.
The various spurs follow:
Nogales spur - Mexican Federal Highway 15 from Mexico City
El Paso spur - Mexican Federal Highway 45 from Mexico City
Eagle Pass spur - unknown, possibly Mexican Federal Highway 57 from Mexico City
Pharr spur - Mexican Federal Highway 40 from Monterrey
Brownsville spur - Mexican Federal Highway 101 from Ciudad Victoria
From Mexico City to the border with Guatemala, the Highway follows Mexican Federal Highway 190.
Through the Central American countries, it follows Central American Highway 1, ending at Yaviza, Panama at the edge of the Darién Gap.
The road had formerly ended at Cañita, Panama, 110 miles (178 km) north of its current end.
United States government funding was particularly significant to complete a high-level bridge over the Panama Canal, during the years when the canal was administered by the United States.
The southern part of the highway begins in northwestern Colombia, from where it follows Colombia Highway 52 to Medellín.
At Medellín, Colombia Highway 54 leads to Bogotá, but Colombia Highway 11 turns south for a more direct route.
Colombia Highway 72 is routed southwest from Bogotá to join Highway 11 at Murillo.
Highway 11 continues all the way to the border with Ecuador.
Ecuador Highway 35 runs the whole length of that country. Peru Highway 1 carries the Pan-American Highway all the way through Peru to the border with Chile.
In Chile, the highway follows Chile Highway 5 south to a point north of Santiago.
The highway turns east there on Chile Highway 60, which becomes Argentina National Route 7 to Buenos Aires, the end of the main highway.
The highway network also continues south of Buenos Aires along Argentina National Route 3 towards the city of Ushuaia and Cape Horn.
One branch, known as the Simón Bolívar Highway, runs from Bogotá (Colombia) to Guiria (Venezuela).
It begins by using Colombia Highway 71 all the way to the border with Venezuela.
From there it uses Venezuela Highway 1 to Caracas and Venezuela Highway 9 to its end at Guiria.
A continuation of the Pan-American Highway to the Brazilian city of Rio de Janeiro uses a ferry from Buenos Aires to Colonia in Uruguay and Uruguay Highway 1 to Montevideo.
Uruguay Highway 9 and Brazil Highway 471 route to near Pelotas, from where Brazil Highway 116 leads to Rio de Janeiro.
Another branch, from Buenos Aires to Asunción in Paraguay, heads out of Buenos Aires on Argentina National Route 9.
It switches to Argentina National Route 11 at Rosario, which crosses the border with Paraguay right at Asunción.
Other branches probably exist across the center of South America.
The highway does not have official segments to Belize, Guyana, Suriname and French Guiana, nor to the assorted islands in the Caribbean region.
However, highways from Venezuela link to Brazilian Trans-Amazonian highway that provide a southwest entrance to Guyana, route to the coast, and follow a coastal route through Suriname to French Guiana.
Belize was supposedly included in the route at one time, as they switched which side of the road they drive on.
As British Honduras, they were the only Central American country to drive on the left side of the road.
See also Pan-American Highway (North America) and Pan-American Highway (South America) for a detailed description of the highway rout
The Pan-American highway is the subject of a recent (as of 2006) conceptual art piece,
The School of Panamerican Unrest, where Mexican-born artist Pablo Helguera is attempting to drive a portable schoolhouse for the length of the entire route.
The travel writer Tim Cahill
wrote a book, Road Fever, about his record-setting 24-day drive from Ushuaia
in the Argentine province of Tierra del Fuego
to Prudhoe Bay
in the U.S. state of Alaska
with professional long-distance driver Garry Sowerby
, much of their route following the Pan-American Highway