Iquitos, and the Amazon
It's the largest city in the world that has no roads leading in or out. The only ways to get here are by plane (flights from Lima, mostly) or travel by riverboat. When you consider that Iquitos is on the western Pacific side of South America, it is intriguing to think that you can arrive by boat from the Atlantic Ocean, sailing some 2,300 miles from the 200-mile wide mouth of the Amazon all the way to Iquitos, Peru. The Amazon begins at Iquitos, technically speaking, because it is here that the Maranon and Ucayali, major rivers themselves, meet to form what from this point on is named on maps as the Rio Amazonas. And it is here the Amazon makes its unfaltering right-hand turn to the east. These are all facts I had been blithely unaware of.