Guadalupe Peak: Fossil Reef at Eight Thousand Feet

Two hundred fifty million years ago, a warm shallow sea covered what is now southeastern New Mexico and West Texas. In that sea, marine invertebrates, sponges, algae, and mollusks built a reef system roughly four hundred miles long. When the sea retreated and the sediment above the reef was eventually stripped away by erosion, the reef formation was exposed. What you are looking at, rising to eight thousand seven hundred forty-nine feet above sea level, is a piece of that reef.

Guadalupe Peak is the highest point in Texas, and it is a fragment of the Capitan Reef, one of the largest reef complexes in geological history. The same reef system produced the Guadalupe Mountains, the El Capitan escarpment, and the formation that the park takes its name from. In terms of geological scale, this is comparable to the Great Barrier Reef of Australia, now turned on its side and pushed three miles into the sky.

The Mescalero Apache held these mountains through the nineteenth century, using the springs and water pockets in the limestone as reliable sources in the desert below. Their removal in the eighteen eighties, driven by the same Fort Davis campaigns that cleared the Chisos Basin, ended a sustained human presence in the mountains that had lasted for generations.

The peak trail is about eight and a half miles round trip, with about three thousand feet of elevation gain. Most people who drive through here do not summit. The view from the Guadalupe Mountains Visitor Center parking area is itself a good introduction to what a two-hundred-fifty-million-year-old reef looks like when the sea has gone and everything else has worn away.