Los Caballos (in core of the Ouachita Structural Belt)

Santiago Peak stands 6,524 feet high, about 2,700 feet above State Highway 118 nine miles west, an intrusive mass some 35 million years old. Its name has more than one story. One says a small band of Spanish soldiers, meeting a larger party of Indians near the cloud-capped summit, shouted the name of their patron saint and charged. Another tells of a raider named Santiago, chased from San Carlos to the foot of the mountain, who climbed out of reach, shouted "Soy Santiago" at nightfall and was never found.

What the plaque says

Los Caballos (in core of the Ouachita Structural Belt) Highly deformed rocks in the Ouachita Fold Belt, a northeasterly trending range, uplifted about 275 to 290 million years ago. The intricate folding is shown by whitish rock bands--called caballos (the Spanish word for horses)--exposed on both sides of this highway. The Ouachita Fold is comparable in age to the uplift that formed the Appalachians in the eastern part of the United States. The northwesterly trending Del Norte-Santiago range (southmost extension of the Rocky Mountains) forms the southwestern skyline. The rocks of the range were deposited in a sea that coverd the Ouachita Fold Belt after erosion had reduced the highlands and a later submergence lowered the area. Santiago Peak (named for a local man who was killed by Indians and buried beneath the peak) is the high, flat-topped mountain to the southwest. It was once a mass of molten magma that cooled and hardened underneath the earth's surface and was uncovered by later erosion. The Del Norte-Santiago range, uplifted and folded 40 to 60 million years ago, is not half the age of the Ouachita Fold. This is a remarkable fusion of "old" and "young" mountains--and is unmatched at any other site in North America. (1970)

Where it stands

Worth the stop nearby

• Museum of the Big Bend — 30 mi
  The museum of the Big Bend region and northern Mexico on the Sul Ross State University campus in Alpine, back since 2007 in its native-stone building of 1937.

More markers nearby

• Fort Peña Colorada (Red Rock) — 6.1 mi
• Marathon — 10 mi
• Colonel Lewis Given Harman — 11 mi
• Denuded Ouachita Rock Belt — 20 mi