The Isthmus of Tehuantepec in Mexico is the shortest distance between the Gulf of Mexico and the Pacific Ocean. Due to its proximity to major oceanic trading lanes, the isthmus was an important overland route between the Atlantic and Pacific prior to the construction of the Panama Canal.
Proposals for a railway across the isthmus had been made by Mexican authorities in the 1840s, with a concession being granted to the Ministry of War to survey a possible route, but little progress was made during the decade due to funding issues. Following Mexico’s defeat in the Mexican-American War (1844-8), the concession was given to an American company, the Tehuantepec Railroad Company of New Orleans, and a new survey was undertaken under the aegis of chief engineer, John G Barnard, who had become acquainted with the Mexican landscape during the war.
Publishing the results of the survey in 1852, Barnard showed that a route was possible. However, a lack of funding, exacerbated by the construction of a railway across the Isthmus of Panama in 1854 and a financial crash in 1857, led to the collapse of the company in 1860. Interest in the route was revived in the 1870s and a railway was finally completed in 1894. Ongoing issues meant that the line did not become fully operational until 1907. The railway was successful initially, but with the opening of the Panama Canal in 1914, it soon lost much of its business.