The BLM site about the Three Rivers Petroglyph site says this:

“The Three Rivers Petroglyphs are outstanding examples of prehistoric Jornada Mogollon rock art. The basaltic ridge rising above the Three Rivers Valley contains over 21,000 petroglyphs, including masks, sunbursts, wildlife, handprints, and geometric designs. The number and concentration of petroglyphs make this one of the largest and most interesting rock art sites in the Southwest. A rugged 0.5-mile trail begins at the visitor shelter and links many of the most interesting petroglyphs. Another short trail begins on the east side of the picnic area and leads to a partially excavated prehistoric village.

”The Three Rivers Petroglyph Site is one of the few locations in the Southwest set aside solely because of its rock art. It is also one of the few sites giving visitors such direct access to petroglyphs. The number and concentration of petroglyphs here make it one of the largest and most interesting petroglyphs sites in the Southwest. More than 21,000 glyphs of birds, humans, animals, fish, insects and plants, as well as numerous geometric and abstract designs are scattered over 50 acres of New Mexico's northern Chihuahuan Desert. The petroglyphs at Three Rivers, dating back to between about 900 and 1400 AD, were created by Jornada Mogollon people who used stone tools to remove the dark patina on the exterior of the rock. A small pueblo ruin is nearby and Sierra Blanca towers above to the east. A detailed petroglyph guide is available at the Three Rivers Petroglyph Site. “

If you are interested in the geology of the area, go HERE.

With all of the petroglyphs and the rich geological history, this is a COM field trip not to miss. Go to http://www.celebmtns.org/events/2018/three-rivers-petroglyphs for information about taking the trip.