The San Juan Badlands

The San Juan Basin is bordered by the San Juan River to the north, the Chaco River to the west, the San Pedro Mountains to the east, and Indian Road 9 to the south. The western half of the recreation area is fairly flat, with little vegetation. It is the lowest elevation and most desert-like. As you head further east towards Angel Peak, the land rises, forming low hills and deep ravines.


Rocks in the western half of the San Juan Basin are from the Cretaceous period, the last and longest segment of the Mesozoic Era. It lasted approximately 79 million years, from the extinction event that closed out the Jurassic Period until about 65 million years ago when the dinosaurs went extinct. That is the geologic background of the Bisti Badlands.

The rocks on the eastern side of the San Juan badlands are from the Tertiary period, which started 65 million years ago and coincides with mammals taking over the world. The border between these two chapters of the earth’s history is called the ‘K-T boundary.’ US 550 follows that boundary, with fossil records of dinosaur migrations in the badlands to the west and fossil records of megafauna in the badlands to the east.

Angel PeakAngel Peak

Ten thousand acres of pastel-colored badlands, cliffs and dry washes surround Angel Peak. At 6,988 feet, the peak is considered a minor summit. The barrenness of the surrounding landscape is due to high soil alkalinity and poor drainage, which inhibits almost all vegetation.

The erosion of three strata produced the badlands around Angel Peak; Kirtland Shale, the San Jose Formation and the Nacimiento Formation. The Nacimiento Formation formed over millions of years. The Inland Cretaceous Sea covered much of the region. Ancient rivers deposited hundreds of feet of rock, sand and other materials into the San Juan Basin. These rivers originated in the high grasslands, swamps, marshes, lakes, and forests further north. Over millions of years, spring flooding washed layer upon layer of sandstone, siltstone, and mudstone downstream. The spire of Angel Peak was part of the San Jose Formation, a much denser layer of sandstone deposited after the Nacimento Formation.

Erosion created the bizarre landscape of the badlands. It is an ongoing process. Wind and water continue to sculpt the mudstone, siltstone and sandstone layers at Angel Peak, occasionally yielding new fossils. The fossilized remains of fish, lizards and crocodiles are embedded in the rock and petrified wood protrudes from the canyon walls. Paleontologists collect, study and document fossil finds from this area to garner more insight into the earth’s history and the evolution of mammals.

Angel Peak Recreation AreaRecreation Area

The badlands are desolate, peaceful, solitary places. It is more common to encounter a snake than a human. Cell phone reception is spotty on a good day. Waiting for a human to help with accidents or mishaps could be problematic or fatal. Pack accordingly.

The Bureau of Land Management is responsible for the protection and preservation of the Angel Peak Recreation Area and surrounding badlands. The area is open to the public, with free campsites available on the rock promontories overlooking the badlands. There are several paths leading into the badlands from the campsites, including a trail to the summit of Angel Peak.

The undulating scenery around Angel Peak lacks the impressive hoodoos found elsewhere in the San Juan basin. The area isn’t as photogenic as the Bisti, but there are outstanding photo opportunities, particularly at sunrise and sunset. The banded colors of the cliffs and the canyon at the base of Angel Peak are only visible from the trail along the rim, which is a short hike from the camping area.

Other attractions nearby include the Bisti/De-Na-Zen Badlands, Chaco Canyon, several Ancestral Puebloan ruins, and over 300 natural arches around Aztec. The nearest towns with hotels are Bloomfield (15 miles), Aztec (22 miles) and Farmington (25 miles).

Map of the San Juan Basin
Map of the San Juan Basin

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