The Traveler at Home: State Road 4

Beefsteak Hill

When I first came to this state, I bought Halka Chronic's book, Roadside Geology of New Mexico. Her books were always  informative for us curious people who wanted to know more about the amazing scenes we were driving through.

But the NM book left me upset because one of the prettiest drives in the state wasn't even mentioned, the road from San Isidro north to Jemez Springs, and on to Los Alamos. State Road 4.

I travel this road a lot and remembered a particular hill being referred to as Beefsteak Hill by Dr. John Callender, the geologist who was instrumental in establishing the NM Museum of Natural History. I was a docent there, in the 1980s and went on several docent trips, plus I took a class from Dr. Callender through the UNM in Albuquerque.

Beefsteak hill dominates the landscape north of San Isidro. In the light of the rising sun it is deep red, like a rare steak, but by afternoon, cast into deep shadow, it is just another pretty hill to look at, nothing spectacular. It is the first formation one sees of the deep red sandstone that dominates the scenery further north. I believe it is part of the Entrada Sandstone formation, that was once ocean bottom, laid down during the Jurrasic period, 140 to 180 million years ago. Sitting on top of it, further up the valley, is volcanic tuff deposited from the Jemez Volcano which last exploded just over one million years ago.

State Road 4, as it passes through Jemez Canyon,
Entrada Sandstone topped with volcanic tuff
(No I didn't tweak the colors!)

As the road runs north it passes by Jemez Pueblo and through some of the darkest red rocks on this continent. Just north of the pueblo, there is a visitor's center, and across the highway, the pueblo has built a large picnic and ceremonial area with red cliffs as the backdrop. On weekends, many tribal members sell baked goods, jewelry, and drums at the permanent stalls that line the road. Their round horno bread is light, crumbly, and delicious. It makes the best French toast on the planet, much better than any French bread on the market.

Underneath all these formations lies a band of hot volcanic rock known as the Jemez Lineament. It is the root of all the volcanos that stretch in a line to the northeast from the caldera of the Jemez volcano. The caldera, known as the Valle Caldera, or the Valles Grandes, is a large bowl-shaped expanse of pastureland surrounded by pine forests, just a few miles further up State Road 4.

Along the route, there are hot springs pouring out into the Jemez river, and a couple feed the commercial bath house in the town of Jemez Springs. It's a fun stop if you have time, very funky though, the bathtubs are concrete casts from the 1930s. In addition, there is a soda dam, a barrier of stone that once stretched all the way across the river from one cliff face to the other. It was cut to make room for the road, but the bulk of the dam is still there and you can park and climb around on it. It was created over eons by hot water that dissolved minerals in the rocks and then deposited them once the water emerged from the mountain in a spring. The hot spring is still there, gurgling out on the side of the road, its water now diverted under the pavement.

At the top of the canyon, where the walls narrow, is a formation called Battleship rock. Viewed head-on it resembles the bow of an enormous ship, but from the side, photographed in the setting sun, one can appreciate all the colors created by the different minerals in the volcanic ash.

Battleship Rock, a formation
of volcanic tuff

State Road 4 leads on past La Cueva, a small village with a motel and good restaurant, up onto the flanks of the Jemez Volcano, past the caldera, and then drops steeply down to the Los Alamos National Laboratory. Another fifteen miles leads through open forest and mesa with extraordinary views of the Sangre de Cristo mountains, Santa Fe glittering to the east, and finally ends after a pass through White Rock.

It is a memorable drive, no matter whether you start in White Rock, or San Isidro. Be sure to take your camera. In the fall, the cottonwoods in Jemez canyon can be spectacular with their golden leaves glittering in the afternoon sun.

A little closer view of Beefsteak Hill,
photographed from the town of San Isidro