Iguassu Falls are famously shared between three nations: Brazil, Argentina and tiny Paraguay (which doesn't actually claim any part of the primary falls, only the rivers). Though the actual Tripitarte, or triple border, lies unmarked at the deepest part of the confluence of the Iguazu and Parana rivers, all three nations have erected monuments—built around obelisks painted patriotically with the colors of their respective flags—overlooking the spot.
Originally erected in 1903, the memorials are built around three simple cement obelisks, painted in the patriotic colors of the three respective flags. The view is nice, and all three monuments are surrounded with vendors selling snacks and souvenirs. The Argentine landmark has the distinction of being the easiest to visit, a pleasant walk from the city center along the riverfront.