Eduardo Gomes International Airport — Manaus, Brazil

Eduardo Gomes International Airport, coded MAO, serves Manaus, a city of well over a million people rising improbably from the middle of the Amazon rainforest at the point where the dark waters of the Rio Negro meet the sandy-colored Amazon River. Manaus owes much of its modern economy to a free trade zone established in the 1960s that turned the once rubber-boom city into an electronics and manufacturing center, a status that keeps MAO busy with cargo and business travel despite its remote location, days by boat from the nearest coastal city. The airport also serves as the jumping-off point for jungle lodges, river cruises, and eco-tourism deeper into the rainforest, an industry that has grown alongside greater international interest in Amazon conservation. Manaus's opulent Teatro Amazonas opera house, built during the rubber boom era of the late 19th century, stands as a striking reminder of the wealth that once flowed through this unlikely metropolis in the jungle.