On our recent trip to Argentina, we took a two-hour flight north to the hamlet of Puerto Iguazú – gateway to one of the most awe-inspiring wonders in South America, if not the world. Iguazú Falls is what happens when the upper Iguazú River plunges almost 300 feet into the lower Iguazú River gorge. Its horizontal span – almost two miles – ranks it the fourth widest waterfall system in the world, behind Khone Phapheng in Laos, Pará in Venezuela, and Kongou in Gabon (note to selves: visit those too!).