Map of the Rio de la Plata and its tributaries, encompassing an area that includes Uruguay, Paraguay, and parts of Brazil, Argentina, Bolivia and Chile. Buenos Aires appears, as do many towns and settlements in the Argentine interior. As yet, there is no city of Montevideo, but we see the mountain for which the city will be named. Courses of the major rivers – the Paraguay, Uruguay and Parana - are shown with good accuracy. The dark, well-drawn cartouche includes figures of natives, river gods, and exotic birds.

Pieter van der Aa was a prolific Dutch mapmaker and publisher working in the early part of the 18th century. His maps, though not original, are sought after for their pleasing decoration. Although his cartographic output was extensive, the atlases seem to have been published in limited quantities, and the result is that his maps are today rather scarce.