The Inter-American Highway is the common name for the section of the Pan-American Highway that runs from Nuevo Laredo in Mexico (close to the border with the US) to Panama City in Panama. For Panamanians, it provides the link to other Central American countries, and beyond, through the Pan-American highway to the USA and Canada. With the Panama Canal, the highway helped contribute to Panama’s position as a crossroads for world trade – though, with the Darien Gap creating a barrier to direct transport links to South America, it is technically a ‘T’ junction, not a crossroads.

There had long been a desire to link the Panama Canal and its associated port facilities with other countries, for the Americans who the operated the Canal, it would reduce the risk of alternative canal proposals being built, by allowing neighboring countries to benefit from its trade links. It would also provide an alternative link to the US Canal Zone, as an alternative to sea crossings.

In 1923, with the agreement of many Central American countries, the US began a project to use their new photo-reconnaissance aircraft to conduct aerial surveys and mapping of the Central American republics. This laid the foundations for a new road, allowing engineers to plan routes and estimate bridging and tunnelling costs. However, it was World War II which spurred construction. Aware of the risks to their supply lines between the USA and the Canal Zone presented by German U-boats, construction of an overland link became a prudent precaution.

As with the final Panama Canal project, construction was led by US engineers and administrators. Many sections of the road that would become part of the Inter-American Highway had been built by individual countries independently before 1940. However, these roads linked specific cities only and were of variable quality. Progress on construction was slow, with multiple obstacles to be overcome and often very remote construction sites. Nevertheless, construction progressed rapidly, though not quickly enough to see the road finished before World War II ended in 1945.

In 1946, a route was ready for inspection by U.S. diplomats and engineers, but it was far from being the finished article, and much was only passable by four-wheel drive or tracked vehicles. It would take until 1967 until the road was completed, and even today, there is no connection beyond Panama, presenting a huge barrier to trade and prosperity in the region.