The petroglyphs of the Spanish conquistadors probably from one of the early expeditions in the 1500s. The location is here in Canyon del Muerto but the precise location needs to be found.
References
Page 464 - Hoig, S., 2013, Came Men on Horses: The Conquistador Expeditions of Francisco Vásquez de Coronado and Don Juan de Onate, University Press of Colorado. 352p.