Sitgreaves Mountain
Rising above the ponderosa pine forests between Flagstaff and Williams, Sitgreaves Mountain is one of the major volcanic summits of northern Arizona’s San Francisco Volcanic Field. Its broad, multi-summited profile reaches approximately 9,392 feet, making it one of the higher mountains on the Coconino Plateau and a conspicuous landmark for travelers crossing northern Arizona on Interstate 40.
Sitgreaves is very different from nearby Kendrick Peak and Bill Williams Mountain. There is no maintained trail to its summit, no lookout tower, and little development. The upper mountain is instead a quiet landscape of forest, grassy openings, steep volcanic slopes, and numerous false summits.
Geologically, Sitgreaves Mountain is especially interesting. Rather than a simple cinder cone, it is a large rhyolite lava-dome complex approximately four kilometers across, surrounded in places by volcanic breccia and accompanied by a younger-looking dacite dome on its southern flank. Its volcanic rocks preserve an important chapter in the evolution of the San Francisco Volcanic Field.
⚡ Fast Facts
| Country | United States |
| State | Arizona |
| County | Coconino County |
| Nearest Community | Parks, Arizona |
| Nearby Cities | Flagstaff and Williams |
| Region | Coconino Plateau |
| Volcanic Region | San Francisco Volcanic Field |
| Elevation | 9,392.4 feet / 2,862.8 meters |
| Prominence | 1,958.2 feet / 596.9 meters |
| Isolation | 9.49 miles / 15.27 kilometers |
| Nearest Higher Neighbor (NHN) | Kendrick Peak |
| Key Col | Approximately 7,434 feet / 2,266 meters |
| Coordinates | 35.34261° N, 112.00626° W |
| USGS Topographic Map | Sitgreaves Mountain |
| Land Management | Kaibab National Forest |
| Mountain Type | Rhyolite lava-dome complex |
| Approximate Age of Summit Dome | 1.9 million years |
| Typical Summit Route | Off-trail hiking |
| Maintained Summit Trail | None |
Older maps and publications commonly list Sitgreaves Mountain at 9,388 or 9,389 feet. Modern LiDAR data places the summit at approximately 9,392.4 feet, making that the more precise figure for the mountain’s high point.
🌋 A Major Volcano of Northern Arizona
Sitgreaves Mountain belongs to the enormous San Francisco Volcanic Field, which covers roughly 1,800 square miles of northern Arizona.
The field contains hundreds of volcanic vents ranging from small basaltic cinder cones to much larger composite volcanoes and lava domes. Volcanism migrated generally eastward through the region over millions of years, leaving a remarkable collection of cones, lava flows, craters, domes, and volcanic mountains across the landscape.
The best-known feature is the San Francisco Peaks north of Flagstaff, crowned by Humphreys Peak.
Farther west, however, several major volcanic centers rise independently above the plateau.
Among the most important are Kendrick Peak, Sitgreaves Mountain, and Bill Williams Mountain.
Together, these large volcanic mountains stand far above the numerous smaller cones scattered across the surrounding forests.
🪨 A Rhyolite Lava-Dome Complex
Sitgreaves Mountain’s geology distinguishes it from many of the basaltic cones of northern Arizona.
The main summit consists of a large rhyolite dome complex approximately four kilometers in diameter. Rhyolite is a silica-rich volcanic rock produced by particularly viscous magma.
Because rhyolitic magma does not flow as freely as basalt, it can accumulate near an eruptive vent and build thick, steep-sided lava domes.
USGS mapping describes the summit rock as light gray to yellowish-gray rhyolite that is strongly jointed. Weathering has broken much of the exposed rock into angular fragments that cover sections of the mountain.
Radiometric dating produced an age of approximately 1.90 ± 0.12 million years for the summit dome.
That places the formation of the main Sitgreaves Mountain dome during the Pleistocene Epoch.
🌋 Volcanic Breccia and the Southern Dome
The mountain is more complicated than a single mass of rhyolite.
A broad breccia collar partly surrounds the summit dome. Breccia consists of broken fragments of rock cemented or accumulated together.
Around Sitgreaves, this material contains pieces of rhyolite, dacite, volcanic ash, basalt, sandstone, limestone, and other rocks. Some of the fragments originated from much older sedimentary formations beneath the volcanic field.
A separate dacite dome also occurs on the southern flank of Sitgreaves Mountain.
Dacite is another silica-rich volcanic rock, intermediate in composition between andesite and rhyolite. The southern dome contains conspicuous crystals of plagioclase, quartz, hornblende, and biotite.
Together, these volcanic units show that Sitgreaves Mountain developed through multiple episodes of magma intrusion and eruption rather than a single simple event.
🧭 Volcanism Along an Ancient Fault System
Sitgreaves Mountain also appears to occupy an important structural line through northern Arizona.
The mountain lies along the Mesa Butte fault system, a northeast-trending zone that extends for more than 120 miles across northern Arizona.
Several major volcanic centers occur along or near this system.
These include Sitgreaves Mountain, Kendrick Peak, and Bill Williams Mountain.
Geologists have suggested that faults and fractures associated with the system may have provided pathways that allowed magma to rise through Earth’s crust, helping determine where these larger volcanic centers developed.
⛰️ Kendrick Peak — The Nearest Higher Neighbor
Sitgreaves Mountain’s Nearest Higher Neighbor is Kendrick Peak.
Kendrick rises to approximately 10,424 feet northeast of Sitgreaves and is one of the tallest independent volcanic mountains in northern Arizona.
Only about 9.5 miles separate Sitgreaves from terrain exceeding its elevation.
Despite that relatively modest isolation, Sitgreaves has almost 2,000 feet of topographic prominence, making it a substantial mountain in its own right.
Its prominence reflects the deep saddles separating the summit from neighboring high terrain. The mountain’s key col sits at roughly 7,434 feet.
🏔️ Sitgreaves and Bill Williams Mountain
To the southwest lies Bill Williams Mountain, another major volcanic landmark.
Bill Williams Mountain reaches approximately 9,260 feet and rises dramatically immediately south of the town of Williams.
Interestingly, Sitgreaves is Bill Williams Mountain’s own Nearest Higher Neighbor.
The two mountains therefore form an important pair on the western side of the San Francisco Volcanic Field.
From openings near the summit of Sitgreaves, Bill Williams Mountain forms one of the most prominent features on the southern horizon.
Farther east and northeast, the much higher San Francisco Peaks dominate the skyline.
🌲 Forests of Sitgreaves Mountain
Dense forest covers much of Sitgreaves Mountain.
At lower elevations, ponderosa pine dominates the landscape. Northern Arizona contains some of the world’s most extensive ponderosa pine forests, and the broad plateau surrounding Sitgreaves is a classic example.
Higher slopes support a cooler and more varied forest.
Quaking aspen becomes increasingly common, particularly in disturbed areas and moist pockets. Douglas-fir and white fir can also occur in the higher forest, creating a mixed-conifer environment very different from the arid landscapes many visitors associate with Arizona.
Grassy meadows and open slopes interrupt the forest in several places.
These openings are especially valuable to summit hikers because the dense tree cover can make navigation surprisingly difficult.
🦌 Wildlife
The forests around Sitgreaves Mountain support many of northern Arizona’s characteristic mountain animals.
Elk are among the largest and most conspicuous residents. The surrounding Kaibab National Forest provides extensive forest and meadow habitat, and elk frequently move through open areas during early morning and evening.
Mule deer are also widespread.
Black bears inhabit northern Arizona’s forested mountains, although sightings are considerably less common. Coyotes, bobcats, gray foxes, porcupines, squirrels, and numerous smaller mammals occupy the surrounding woodland.
Birdlife includes wild turkeys, Steller’s jays, ravens, woodpeckers, mountain chickadees, nuthatches, and several species of raptor.
🥾 Hiking Sitgreaves Mountain
Sitgreaves Mountain is unusual among northern Arizona’s major summits because there is no maintained trail to the top.
That makes the mountain a substantially different undertaking from nearby Kendrick Peak or Bill Williams Mountain, both of which have established hiking routes.
Forest roads provide access to the surrounding country, but the final climb requires off-trail navigation.
Routes vary depending on road conditions and approach. A commonly used northern approach follows a drainage or canyon toward the upper mountain before climbing toward a grassy saddle and then continuing up the final slopes.
Depending on where a vehicle can safely reach, a typical outing may involve roughly five to six miles of hiking and around 2,000 feet of elevation gain.
Exact distances can vary considerably because there is no official summit route.
🧭 Route-Finding Challenges
Navigation is one of the main difficulties of climbing Sitgreaves Mountain.
The broad summit area contains several ridges and false high points. Dense forest can obscure surrounding landmarks, making it easy to drift away from the intended route.
Downed trees and thick stands of young aspen can further complicate travel.
A detailed topographic map, compass, and GPS or offline mapping application are strongly recommended.
Hikers should also mark or carefully remember their return route. Descending through dense forest can be more confusing than climbing because multiple drainages and ridges can appear surprisingly similar.
Arizona Highways described Sitgreaves as a summit reached “without the benefit of a trail,” emphasizing both its solitude and the importance of careful navigation.
🌄 The Summit
The summit of Sitgreaves Mountain is more subdued than the rocky crest its volcanic origin might suggest.
Instead of a dramatic cliff or exposed pinnacle, the highest point lies along a broad, forested upper ridge.
A benchmark marks the summit area.
Because trees surround much of the high point, the summit itself does not always provide completely unobstructed views. Nearby meadows and openings offer better panoramas.
On clear days, hikers can see Bill Williams Mountain to the southwest and Kendrick Peak to the northeast.
Beyond Kendrick rise the much higher San Francisco Peaks.
The vast forested surface of the Coconino Plateau spreads between these volcanic landmarks.
❄️ Seasons and Weather
At more than 9,300 feet, Sitgreaves Mountain experiences a genuine mountain climate.
Winter storms can deposit substantial snow on the upper slopes, and forest roads may become inaccessible for long periods. Winter travel generally requires snowshoes, skis, or other equipment as well as additional navigation experience.
Spring conditions vary considerably from year to year.
Snow and mud can remain on shaded roads and slopes well after lower elevations have dried.
Summer provides warmer conditions, but northern Arizona’s monsoon season introduces frequent afternoon thunderstorms from roughly July through September. Lightning, hail, intense rain, and sudden temperature drops are possible.
Autumn often provides some of the most attractive conditions, with cooler temperatures, relatively stable weather, and brilliant stands of golden aspen.
🍂 Aspen Season
Sitgreaves Mountain is particularly beautiful during the autumn.
Aspen groves scattered across the higher slopes turn vivid shades of yellow and gold, contrasting with the dark green ponderosa pine and fir forest.
Because the mountain receives far fewer visitors than many better-known Flagstaff-area destinations, autumn outings can offer considerable solitude.
Peak foliage timing varies with elevation, temperature, moisture, and seasonal weather, but late September into October is generally the period when northern Arizona’s high-elevation aspens begin showing their strongest color.
🏞️ Kaibab National Forest
Sitgreaves Mountain lies entirely within Kaibab National Forest.
This is worth noting because the mountain’s name can create confusion with the Apache-Sitgreaves National Forests of eastern Arizona.
Sitgreaves Mountain is not located in Apache-Sitgreaves National Forest.
Both the mountain and the historic Sitgreaves National Forest were named for Captain Lorenzo Sitgreaves, a U.S. Army topographical engineer who led an important government exploration across northern Arizona during the early 1850s.
Historical accounts describe his expedition as one of the earliest systematic scientific and topographic explorations of the region.
🧑✈️ Who Was Lorenzo Sitgreaves?
Lorenzo Sitgreaves was an officer in the U.S. Army Corps of Topographical Engineers.
His expedition traveled west through what is now New Mexico and northern Arizona while investigating potential transportation routes and documenting the geography, geology, plants, animals, and Indigenous cultures encountered along the way.
The expedition eventually followed portions of the Little Colorado River and crossed northern Arizona toward the Colorado River.
Sitgreaves’ name subsequently became attached to several geographic features in Arizona, including this mountain.
Nearby Kendrick Peak was named for Major Henry Lane Kendrick, who commanded the military escort associated with the Sitgreaves expedition.
🌋 Part of a Remarkable Volcanic Landscape
Sitgreaves Mountain makes the most sense when viewed as part of the broader volcanic landscape surrounding Flagstaff.
To the east, Humphreys Peak and the San Francisco Peaks represent the remnants of an enormous stratovolcano.
Elden Mountain is another prominent lava dome near Flagstaff.
To the northeast and east are hundreds of younger cinder cones, including the dramatically preserved Sunset Crater.
Westward stand Kendrick, Sitgreaves, and Bill Williams Mountain.
Together, these features reveal millions of years of volcanic activity across the southern Colorado Plateau.
The San Francisco Volcanic Field remains geologically young. Its most recent eruption occurred at Sunset Crater approximately 900 years ago, demonstrating that volcanic activity in northern Arizona is not merely an ancient phenomenon.
🌄 Why Sitgreaves Mountain Is Special
Sitgreaves Mountain lacks the dramatic summit cliffs of some Arizona peaks and the maintained hiking trails of its better-known neighbors.
That is precisely part of its appeal.
The mountain offers a quieter experience: a broad volcanic summit hidden within deep forest, where route finding matters more than following trail signs and where hikers may spend hours without encountering another person.
Its geology is equally compelling.
A two-million-year-old rhyolite dome, volcanic breccia, dacite intrusions, and connections with a major regional fault system make Sitgreaves much more than another forested high point.
Combined with nearly 2,000 feet of prominence, sweeping views toward Kendrick Peak, Bill Williams Mountain, and the San Francisco Peaks, Sitgreaves Mountain is one of the most interesting lesser-known summits of northern Arizona.
🔗 Related Articles
- Kendrick Peak (Arizona)
- Bill Williams Mountain
- San Francisco Peaks
- Humphreys Peak
- Elden Mountain
- Agassiz Peak
📚 Sources
- Peakbagger — Sitgreaves Mountain
- U.S. Geological Survey — Geologic Map of the Central Part of the San Francisco Volcanic Field
- U.S. Geological Survey — San Francisco Volcanic Field
- U.S. Geological Survey — Bright Angel and Mesa Butte Fault Systems of Northern Arizona
- Arizona Highways — Climbing Sitgreaves Mountain
- HikeArizona — Sitgreaves Mountain
