General Carrera — shared with Argentina, where it's known as Lago Buenos Aires — is one of the largest lakes in South America, an enormous sheet of glacial water so clear and blue that boat trips to the marble caves near Puerto Río Tranquilo have become an attraction in their own right. That clarity and scale shape the fishing: big brown and rainbow trout cruise the drop-offs, river mouths and wind-exposed points, and covering water from a boat matters more here than almost anywhere else in the region. Woolly Buggers, bunny leeches and zonkers stripped along structure are the standard flies. The lake can turn from glassy to genuinely dangerous within an hour when the wind comes up off the ice fields, so respect for conditions matters as much as fly choice.

• Lake
• Glacial