The first fully solar-powered luxury train in Latin America is rolling into the station: Argentina’s Tren Solar de la Quebrada. It’s been operational for about two years now, but the Quebrada solar train, located in the province of Jujuy, is still attracting new fans and tourists. The train can hold up to 388 passengers, with 72 seated, and is powered by a 352-kilowatt-hour battery pack. This, along with “regenerative braking” on downhill parts of the journey, easily accommodates the standard 52-mile round trip on one charge. That said, each of the six stations on the route has EV-style chargers for the train to charge up, in the event that it needs more juice. There is no combustion engine anywhere on the vehicle. Not only does the passenger train emit no noise or emissions, but its 26-mile route connects one of UNESCO’s World Heritage Sites. Departing from the village of Volcán, the two-car train cuts through Quebrada de Humahuaca, known as one of South America’s oldest cultural corridors. Clocking in at about 10,000 years old, the ancient canyon was a trade route first traveled by hunter-gatherers, and later, Indigenous traders, Inca messengers, Spanish colonists, and railway workers. Over the course of history, the route has been a constant, and now it merges that long lineage with modern solar power innovation. The route is lined with stunning rock formations and red hillsides that make for gorgeous views. “Quebrada de Humahuaca follows the line of a major cultural route, the Camino Inca, along the spectacular valley of the Rio Grande, from its source in the cold high desert plateau of the High Andean lands to its confluence with the Rio Leone some 150 kilometers to the south,” UNESCO describes the valley on its world heritage profile. “The valley shows substantial evidence of its use as a major trade route over the past 10,000 years. It features visible traces of prehistoric hunter-gatherer communities, of the Inca Empire, and of the fight for independence in...