Nothing will prepare you for the nearly 200-foot-high wall of blue ice that awaits in Laguna San Rafael, a UNESCO World Biosphere Reserve celebrated for its otherworldliness. The world’s lowest-latitude tidewater glacier, Ventisquero San Rafael descends from the Campo de Hielo Norte and meets the frigid waters of Laguna San Rafael, where massive chunks calve off and become indigo icebergs. While the biodiverse wilderness has remained mostly unchanged since John Byron – grandfather of the famous poet Lord Byron – was famously shipwrecked here in the 18th century, the glacier itself has been in continuous retreat since 1960. Climate change is expected to hasten its retreat.