1985 Map of San Ygnacio

About this map

The Rio Grande serves as the international boundary between Texas and Tamaulipas in this 1980s-era topographical record of the borderlands. The landscape is defined by its drainage network, with dozens of named arroyos such as Arroyo Agua Azul and Arroyo Chargos feeding into the river. On the American side, the settlement pattern centers around the Texas Mexican RR corridor in the north, where small communities like Aguilares and Reiser are located, and along U.S. 83 which parallels the river down toward San Ygnacio.