El Camino Real

The villages of the Adai at that time extended from the Red River southward beyond the Sabine into Texas, and the latter stream was known in the 18th century as Rio de los Adais. The trail between some of their villages became part of the road between Natchitoches and San Antonio, known variously as the “Contraband Trail,” San Antonio Trace, and El Camino Real, which passed through Los Adaes.
Dr. Clarence H. Webb
"The Belcher Mound, A Stratified Caddoan Site in Caddo Parish, Louisiana," Society for American Archaeology, 1959