But the meadow and surrounding country were privately owned until 2000, when the Valles Caldera Preservation Act allowed the federal government to buy 89,000 acres of the Baca Ranch for addition to the National Forest system. Plans for public access began to form, and this past July, the Valles Caldera opened for the first time to riders.
That huge "bowl" visible from the highway is still off-limits, though, earmarked for elk and cattle grazing. Only the resident ranch foreman and his range riders may ride across it. But there are other craters designated just for outside riders: the El Cajete meadow and Redondo meadow.
After saddling at an 8,400-foot elevation, I ride into a ponderosa-pine forest in the Jemez Mountains, navigating a logging road that dates to the early 1900s. For 3 miles, I'm in deep woods, taking in clean air, listening to the occasional birdsong and the rustle of shifting branches and small animals scurrying in the underbrush. The mountains can be glimpsed through the pines.
Ahead lies a meadow - El Cajete, or "the washtub" - where the grass is higher than my horse's belly, a rare sight in the drought-stricken West. Along the meadow's rim, ponderosa and aspen reach skyward.
The grass and wildflowers all flow into a sea of colors - red, white, yellow, orange and various shades of green that shimmer through El Cajete. It's heaven for my horse, who snatches mouthfuls of grass as I ride.
In the mornings, elk graze in this meadow, their calves asleep, hidden in the tall grass.
This quiet meadow is actually a volcanic crater. Volcanic activity beginning about 16 million years ago formed the Jemez Mountains in north-central New Mexico. The Jemez range can be described as giant piles of different types of lava, with a deep impression - the cliff-ringed, 14-mile-wide Valles Caldera - at the center of the pile.
The Working Ranch
Grazing, logging and geothermal exploration have all left their marks on the Valles Caldera. During the 1920s, the area was used as a summer camp for boys.
The Valles Caldera National Preserve is committed to maintaining the property as a working ranch, running a sustainable number of livestock and adjusting herd numbers based on range assessments.
"The Caldera is so large, there are going to be many years of finding new resources," suggests Eldon Reyer, a former National Park Service guide who's explored the caldera extensively. Reyer helped prepare the legislation that established the nearby Bandelier National Wilderness and helped make preservation of the caldera possible.
Now retired from the NPS, Reyer lives in nearby Santa Fe and is president of the Northern New Mexico Horseman's Association.
"I was having flashbacks while riding in the caldera," he says. "All I could think of was how I'd like to be a ranger there again."
For the safety of riders, the preserve's parking area is closed at 11 a.m. Ron Breines, equestrian-program manager and a local horse trainer, stays onsite while visitors ride, and will go in search of riders who might be lost or in trouble.
Riders are advised to arrive early (gates open at 8 a.m.) and must be back from their rides by 3 p.m. in the summer because of lightning, 4 p.m. in the spring and fall. A "staging area" has spaces for up to eight four-horse trailers. An on-site manager can provide riders with maps and an orientation.
Because the preserve is still in an experimental stage, riders have an opportunity to offer input.
"We've worked with a group of knowledgeable equestrians to create a program that will work for horse owners," says Dennis Trujillo, the preserve's manager. "What we learn this year will be applied next year."
There are plans to add more equestrian trails, to extend the number of days riders can use the area, and add horse camping and a visitor's center. Currently, each area of the Caldera open to the public is devoted to a particular use; there's no overlap of hikers and equestrians, for instance.
Before making plans to visit the Valles Caldera, call 877-851-8946, or visit www.vallescaldera.gov. A fee of $20 per horse applies.