Inter-American Highway

The Inter-American Highway (IAH) is the Central American section of the Pan-American Highway and spans 5,470 kilometers (3,400 mi) between Nuevo Laredo, Mexico, and Panama City, Panama.

The idea of a road being built across all of Central America became a tangible goal in 1923 as the United States began conducting aerial surveys using the United States Army new photo reconnaissance and photographic aerial mapping technology. However, the aerial mapping effort was not directly tied to the upcoming Inter-American Highway project and was conducted with the cooperation of several of the Central American republics.

By 1940, the United States had a strong presence in Central America, especially in Panama. The American-owned and operated both the Panama Canal and the Panama Railroad, but with the looming war in Europe, the United States felt it necessary to establish a more direct connection with Panama. Therefore, the American and Panamanian governments agreed to begin the construction of a trans-isthmian highway located outside of the Canal Zone. Thus, the construction of the actual Inter-American Highway was instigated by the United States as a safety precaution at the beginning of World War II.

As with the Panama Canal project, the principal engineers and administrators of the highway construction were supplied by the United States. Working and living conditions varied depending on the location and season, but they were described by the North American crew as "primitive" and they recall their experiences as both "hilarious and tragic." For those stationed in larger cities, their families were allowed to come and stay with them as an incentive to keep them from returning to the United States.

Many pieces of what is now the Inter-American Highway were constructed independently by individual countries prior to 1940. However, these roads only existed between large cities and were not in very good condition. Unlike in the United States, transportation in Central America had progressed rapidly from ox-cart paths to air transport creating numerous gaps in the ground transportation network. One of the greatest challenges faced by the workers was bridging these gaps.

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