1 Aguaverde: A Forgotten Presidio of the Line, 1773-1781 Solveig A. Turpin and Herbert H. Eling, Jr. (originally published in the Journal of Big Bend Studies 16: 83-128 Sul Ross State University, Alpine) Abstract A preliminary survey of the ruins of Presidio Santa Rosa Maria del Sacramento de Aguaverde (1773-1781) and later Colonia Militar San Vicente (1851-1853) produced a map of the perimeter walls, exposed the outlines of one bastion store room and an isolated structure, and listed artifacts visible on the surface and in treasure hunter holes. Archival records provide a history of the founding and abandonment of three incarnations of the presidio. Construction of the first Presidio Sacramento began on the San Diego River in 1737 but ceased in 1739 when the garrison was moved to the Santa Rosa valley. In 1773, orders to restructure the presidial line resulted in the founding of a presidio at the spring called Aguaverde, a tributary to the San Diego River. The fort was abandoned in 1781, only to be recommissioned as a Colonia Militar by the Mexican government for a brief two years between 1851 and 1853. Subsequently, the site was plundered for building material and damaged by treasure hunters and construction of a transmission line through its main compound. Introduction Presidio Santa Rosa María del Sacramento de Aguaverde (1773-1781) is one of the forgotten presidios of the line established in 1773 in a vain attempt to protect the communities and ranches of northern New Spain (Figure 1). For well over a century, northward expansion of the Spanish empire was thwarted by the hostility of the native people and the inhospitable land that was their refuge. By the early 18 th century, the routes north had bifurcated, the eastern prong passing through fortified San Juan Bautista en route to San Antonio and the western leading to Santa Fe through El Paso del Norte. In between lay the arid Bolsón de Mapimí, the stern and unforgiving northern ranges of the Sierra Madres, and the agonizingly steep canyons of the Río Grande. Although unfit for European colonization, the despoblado, or unpopulated zone, was both a haven and a highway for the native insurgents who penetrated Spanish defenses in search of plunder and revenge. Just as the Spanish colonial movement detoured around the harsh and intractable terrain of northern Coahuila, so has archeological and historical research circled around the lonely short-lived presidios of the line that once guarded the northern frontier of New Spain from the southern banks of the Rio Grande. Rex Gerald’s (1968) Spanish Presidios of the Late Eighteenth Century in Northern New Spain examined presidial architecture and artifacts from