This early-18th century map of the valley of the Orinoco River contains extensive information about the Indian nations bordering the river, Christian missions and other settlements, the extensive array of streams that flow into the Orinoco, and navigational hazards and islands. The map includes a keyed index and a detailed historical note on the exploration of the river from 1682 to 1732. The note records information about the martyrdom of several religious figures. As indicated in the note, much of the information for the map came from different religious sources (for example, Fray Silbestre Hidalgo, an Augustinian priest), as well as military and government sources. The map and the note exemplify the common practice of the Spanish of gathering information about the cultures, people, and geography of their newly-acquired lands in America. The map is oriented with southwest at the top. It is part of the Library of Congress’s collection from the Real Escuela de Navegación, Cadiz, Spain, purchased from Maggs Brothers, London.