San Antonio Mountain is a large, free-standing mountain in northern New Mexico. This dome-shaped mountain rises in relative isolation above sagebrush flats about nine miles south of the Colorado border. The rounded volcanic dome of San Antonio Mountain is a major landmark along US-285 and is located at the southern end of the scenic San Luis Valley.

The summit of the mountain is located in the Carson National Forest, but other areas of the mountain are on Bureau of Land Management, state, and private property. San Antonio Mountain appears as an almost perfectly symmetrical dome from certain angles. However, other angles reveal two distinct summits: the 10,890’ Antone Peak, and the 10,908’ San Antone Peak. Together, they form San Antonio Mountain. There are several radio towers at the summit, and a road leads up to them. San Antonio Mountain is the highest of the numerous cinder cone peaks in the area.

From the town of Tres Piedras on US-285, drive north about 14 miles to the southeast slopes of San Antonio Mountain. You will then see a prominent road that heads west up the mountain. Turn left onto the road. You will now be on BLM land. However, you will immediately see a sign that says “Road Closed ½ Mile Ahead”. Drive up the road a short distance and park.

You can drive all the way to the locked gate, but it may be better to park further down the road. Private property is located past the locked gate. All of San Antonio Mountain is located on public property, except for this one square mile area of private property along the road. This road turns into Forest Road 418 after it passes through the private property and enters the Carson National Forest.