the lands located between the existing town of san francisco de conchos and the confluence of the río concho and río florido rivers were explored by francisco escárcega on june 12, 1687, at the direction of the governor of nueva vizcaya, don josé de neyra y quiroga. in 1740, the site at the confluence of the río concho and río parral rivers was established as a town with the name of santa rosalía for the catholic missionaries who were assigned to administer in the area.