The Pan-American Highway is a network of roads measuring about 30,000 kilometres (19,000 mi) in total length. Except for a rainforest break of approximately 100 km (60 mi), called the Darién Gap, the road links almost all of the mainland countries of the Americas in a connected highway system. According to Guinness World Records, the Pan-American Highway is the world's longest "motorable road". However, because of the Darién Gap, it is not possible to cross between South America and Central America.
Jake Silverstein, writing in 2006, described the Pan-American Highway as "a system so vast, so incomplete, and so incomprehensible it is not so much a road as it is the idea of Pan-Americanism itself".
The concept of an overland 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, this proposal was never realized. The idea of building a highway emerged at the Fifth International Conference of American States in 1923. The first conference regarding construction of the highway occurred on October 5, 1925. Finally, on July 29, 1937, Bolivia, Chile, Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, Canada, and the United States signed the Convention on the Pan-American Highway, whereby they agreed to speedy construction, by all adequate means. In 1950, Mexico became the first Latin American country to complete its portion of the highway.