Tempe Butte
Rising immediately above downtown Tempe and the Arizona State University campus, Tempe Butte is one of the most recognizable urban mountains in the Phoenix metropolitan area. Better known locally as “A” Mountain and also called Hayden Butte, this compact desert summit reaches approximately 1,498 feet (457 meters) above sea level.
Although Tempe Butte rises only about 350 feet above the surrounding Salt River Valley, its isolated position gives hikers remarkably expansive views across Tempe, Phoenix, Papago Park, and the mountains surrounding the Valley of the Sun.
The mountain is also much more than a popular hiking destination. Tempe Butte contains hundreds of ancient petroglyphs, preserves evidence of the region’s Indigenous history, has played an important role in the development of modern Tempe, and is closely associated with Arizona State University.
Today, much of the mountain is protected as Hayden Butte Preserve, where visitors can follow a short but steep trail toward the summit while exploring one of the most historically and culturally important landforms in the city.
⚡ Fast Facts
| Feature | Details |
|---|---|
| Mountain | Tempe Butte |
| Other Names | Hayden Butte, “A” Mountain |
| Elevation | 1,498 ft (457 m) |
| Prominence | 325 ft (99 m) |
| Isolation | 2.64 mi (4.25 km) |
| Coordinates | 33.42824° N, 111.93577° W |
| Location | Tempe, Maricopa County, Arizona |
| Region | Phoenix Metropolitan Area |
| Nearest Higher Neighbor (NHN) | Papago Big Butte |
| Rock Type | Primarily andesite over sedimentary rocks |
| Volcanic Rock Age | About 17.6 million years |
| Protected Area | Hayden Butte Preserve |
| Preserve Size | About 25 acres of city park/preserve |
| Best Known Feature | 60-foot “A” |
| Best Time to Hike | Fall through spring |
🏜️ Where Is Tempe Butte?
Tempe Butte rises directly beside downtown Tempe, Arizona, immediately north of much of the Arizona State University campus.
The mountain is bordered by some of the city’s best-known landmarks. Mill Avenue lies to the west, the Salt River and Tempe Town Lake are immediately to the north, and the Arizona State University campus spreads south of the butte.
Mountain America Stadium, historically known as Sun Devil Stadium, occupies a saddle along the eastern side of the mountain.
This extraordinarily urban setting makes Tempe Butte unusual among Arizona summits. A hiker can leave the restaurants, shops, university buildings, and light-rail stations of downtown Tempe and begin climbing desert terrain within minutes.
Despite the surrounding development, the butte remains an important pocket of native Sonoran Desert habitat.
⛰️ How High Is Tempe Butte?
Tempe Butte reaches approximately 1,498 feet above sea level according to lidar-based elevation measurements.
Its base is around 1,150 feet, giving the mountain roughly 350 feet of local relief.
Peakbagger calculates its topographic prominence at approximately 325 feet and its isolation at 2.64 miles.
Those numbers may seem modest compared with mountains such as Piestewa Peak or the larger peaks east of Phoenix, but Tempe Butte’s isolation makes it appear surprisingly prominent from the surrounding city.
It essentially rises as an island of rock above the otherwise developed Salt River Valley.
🏔️ Nearest Higher Neighbor
Tempe Butte’s Nearest Higher Neighbor is Papago Big Butte, located roughly north-northwest in nearby Papago Park.
The two mountains are closely connected geographically.
Papago Big Butte reaches about 1,673 feet, while Tempe Butte tops out just below 1,500 feet. The low desert terrain between the two explains Tempe Butte’s relatively substantial 325 feet of prominence.
Both mountains also stand as isolated natural landmarks surrounded by the Phoenix metropolitan area, although their geology is quite different.
Papago’s famous rounded formations are composed largely of sedimentary rock and conglomerate, while Tempe Butte is capped by much harder volcanic andesite.
🌋 Is Tempe Butte a Volcano?
Tempe Butte has a volcanic origin, but describing the modern mountain simply as an extinct volcano can be misleading.
The butte contains substantial layers of andesite, a volcanic rock produced from intermediate-composition lava.
Geologic mapping of the Tempe area places the andesite at approximately 17.6 million years old.
The volcanic rocks lie above older sedimentary deposits that include sandstone and related materials. Rather than representing a perfectly preserved volcanic cone, the modern mountain is an eroded and tilted block of ancient rock.
Faulting, uplift, tilting, and millions of years of erosion gradually produced the landform visible today.
🪨 Geology of Tempe Butte
Tempe Butte provides an excellent window into the complicated geological history of the Phoenix Basin.
The mountain’s resistant upper layers consist largely of andesitic lava flows. Beneath them are sedimentary rocks deposited during earlier episodes of basin development.
Arizona Geological Survey mapping indicates that the andesite dates to approximately 17.6 ± 0.4 million years ago.
During the middle part of the Cenozoic Era, central Arizona underwent extensive faulting and crustal extension. Mountain blocks were uplifted while adjacent basins subsided.
Tempe Butte became one of several small tilted and uplifted blocks that now protrude through the thick layers of sediment filling the Phoenix Basin.
Nearby Papago Park and other isolated rock outcrops preserve related pieces of this enormously complicated geological history.
The harder volcanic rocks resisted erosion better than much of the surrounding material, helping Tempe Butte survive as an isolated hill while the basin around it filled with sediments.
🥾 Hiking Tempe Butte
Tempe Butte is one of the most popular short hikes in Tempe.
The main route climbs through Hayden Butte Preserve toward the summit area. Portions of the route are paved or improved, but the trail becomes steep enough to provide a surprisingly good workout for such a small mountain.
Expect roughly 300 to 350 feet of climbing, depending on where you begin and how far you explore.
Metal railings and constructed sections assist hikers on portions of the route.
The climb is short enough to fit easily into a morning or evening visit, but Phoenix-area heat should never be underestimated. During hot weather, temperatures on the exposed slopes can become dangerous very quickly.
The City of Tempe requires visitors to remain on designated trails to protect fragile desert vegetation, archaeological resources, and ancient rock art.
🌄 Views From the Summit
The reward for the short climb is an outstanding panorama of the central Phoenix metropolitan area.
Looking north, hikers can see Tempe Town Lake and the Salt River corridor.
To the northwest are the distinctive red formations of Papago Park, including Papago Big Butte.
Beyond them, the mountains of Phoenix rise above the city. Piestewa Peak and the broader Phoenix Mountains are prominent landmarks on clear days.
To the east, the skyline opens toward Mesa and the distant desert mountains, while downtown Tempe and Arizona State University spread immediately below the southern slopes.
Sunrise and sunset can be especially beautiful, when low-angle light illuminates the desert mountains surrounding the Valley.
🅰️ Why Is It Called “A” Mountain?
Tempe Butte’s most visible human-made feature is the enormous gold “A” on its southern slope.
The letter stands approximately 60 feet tall and represents nearby Arizona State University.
However, the mountain did not always display an A.
Students from the Tempe Normal School installed an “N” on the mountain in 1918. When the institution became Tempe State Teachers College, the N was eventually changed to a “T.”
An “A” first appeared in 1938 and became associated with the school’s evolving identity.
After an earlier version was destroyed by vandals, a reinforced steel and poured-concrete A was built during the 1950s. That structure remains one of the most visible symbols of Arizona State University.
Painting the A has since become part of ASU tradition, particularly around major university events.
🪶 Indigenous History and Sacred Landscape
Tempe Butte has cultural importance stretching back far beyond the creation of the modern city.
People associated archaeologically with the Hohokam tradition lived throughout the Salt River Valley for centuries. A major settlement known today as La Plaza once stood near the base of the mountain.
The butte contains approximately 500 recorded petroglyphs, many created between roughly A.D. 750 and 1450.
Images include human-like figures, animals, geometric forms, and other designs whose meanings may have held spiritual, social, or territorial significance.
The City of Tempe recognizes Hayden Butte as sacred to contemporary Indigenous communities of the region, including the Salt River Pima-Maricopa Indian Community and other Four Southern Tribes of Arizona.
These archaeological and cultural resources are among the most important reasons visitors must stay on established trails and never touch, trace, chalk, scratch, or otherwise alter petroglyphs.
Once damaged, ancient rock art cannot truly be restored.
🏺 La Plaza and the Hohokam
Archaeological discoveries around the base of Tempe Butte reveal that this was once part of a substantial Indigenous settlement.
The Hohokam created one of the most sophisticated irrigation systems in prehistoric North America, digging hundreds of miles of canals through the Salt River Valley.
These canals supported communities that cultivated crops including corn in a landscape where reliable rainfall was limited.
La Plaza developed near Tempe Butte and the Salt River, taking advantage of the same basic resources that would later attract settlers to the region.
Archaeological excavations associated with modern transportation and construction projects have uncovered evidence of this earlier community.
The mountain therefore provides a physical connection between today’s city and a human history extending back well over a thousand years.
🏘️ Charles Hayden and the Development of Tempe
The name Hayden Butte honors pioneer businessman Charles Trumbull Hayden, one of the most important figures in Tempe’s early development.
Hayden recognized the economic possibilities of the Salt River crossing during the nineteenth century and established businesses in the area.
His enterprises eventually included a ferry across the Salt River, a store, and the Hayden Flour Mill near the western base of the butte.
A community called Hayden’s Ferry grew nearby.
Another settlement, San Pablo, developed east of Tempe Butte.
These communities eventually helped form modern Tempe.
Hayden Butte therefore became more than simply a geographical landmark—it stood at the center of the area’s transition from Indigenous agricultural landscape to nineteenth-century settlement and eventually to a major modern city.
🏟️ Sun Devil Stadium and the Mountain
Human development has substantially changed portions of Tempe Butte.
One of the largest alterations occurred during construction of Sun Devil Stadium in 1958.
The stadium was designed to occupy a natural saddle between portions of the butte, and part of the eastern side of the mountain was excavated during construction.
Today, the stadium—now officially Mountain America Stadium—is so closely incorporated into the landscape that the mountain frequently forms the backdrop to Arizona State football games.
The combination of university, stadium, historic downtown, desert preserve, and mountain terrain makes Tempe Butte unlike almost any other summit in Arizona.
🌵 Plants and Wildlife
Despite being surrounded by dense urban development, Hayden Butte Preserve retains a surprisingly diverse collection of Sonoran Desert vegetation.
Plants found on and around the butte include saguaro cactus, barrel cactus, buckhorn cholla, creosote bush, palo verde, mesquite, desert lavender, Mormon tea, wolfberry, and catclaw acacia.
Wildflowers may appear after favorable winter rainfall, particularly during late winter and early spring.
Small desert animals also survive within the preserve. Rabbits, rodents, reptiles, birds, and other species use the mountain as a habitat island amid the surrounding city.
Preserving even relatively small natural areas like Tempe Butte can therefore provide important refuges for urban wildlife.
🏞️ Hayden Butte Preserve
The City of Tempe began formally protecting the mountain decades ago.
Tempe Butte was designated as a park during the 1970s and later became the city’s first official preserve in 2002.
The protected city park encompasses approximately 25 acres, while the broader butte itself covers a larger area.
The mountain was also listed on the National Register of Historic Places in 2011, recognizing its exceptional archaeological, cultural, geological, and historical importance.
Preserve rules are designed to protect these resources.
Visitors should remain on marked trails, avoid disturbing rock formations or vegetation, leave petroglyphs untouched, carry out all trash, and avoid biking on hiking trails where bicycles are prohibited.
☀️ Best Time to Hike Tempe Butte
The most comfortable season for hiking Tempe Butte is generally October through April.
Winter typically brings mild daytime temperatures ideal for short desert hikes.
February through April can be especially attractive when favorable rainfall produces wildflowers across the slopes.
Summer is far more challenging.
Tempe regularly experiences temperatures well above 100°F, and Tempe Butte offers very little shade. Even though the hike is short, heat illness can occur rapidly.
If visiting during warmer months, early morning is generally the safest part of the day. Carry more water than you expect to need and avoid hiking during periods of extreme heat.
The preserve is currently listed by the City of Tempe as open from 6 a.m. to 10 p.m., although visitors should check current city information before planning a trip.
📸 Best Time for Views and Photography
Sunrise and sunset transform Tempe Butte into one of the best easily reached viewpoints in the city.
Morning light can illuminate downtown Tempe and the surrounding mountains, while sunset often creates dramatic silhouettes across the Phoenix skyline.
The mountain is also an excellent location for photographing the contrast between desert terrain and urban development.
From a single viewpoint, photographers may capture cactus-covered slopes, university buildings, Tempe Town Lake, downtown high-rises, aircraft approaching Phoenix Sky Harbor International Airport, and distant desert mountains.
Few hikes illustrate the meeting of natural and urban Arizona quite so clearly.
🌟 Why Tempe Butte Is Special
Tempe Butte is not high by Arizona standards.
It does not have the dramatic elevation of the San Francisco Peaks, the rugged profile of the Superstition Mountains, or the physical challenge of Piestewa Peak.
Yet few Arizona mountains combine so many layers of history within such a small area.
Its rocks record volcanic activity nearly 18 million years ago. Its slopes preserve hundreds of Indigenous petroglyphs. Its location influenced early settlement beside the Salt River. Its giant A reflects nearly a century of Arizona State University tradition.
And today, its trails allow hikers to climb from the heart of a modern city into a pocket of remarkably intact Sonoran Desert landscape.
For such a small summit, Tempe Butte carries an extraordinary amount of Arizona’s geological, cultural, and urban history.
🔗 Related Articles
📚 Sources
- Peakbagger — Tempe Butte, Arizona
- City of Tempe — Hayden Butte Preserve
- City of Tempe — Hayden Butte Preserve Park / A Mountain
- City of Tempe — Rock Art at Hayden Butte
- City of Tempe — Hayden Butte Preserve Park Information
- Arizona Geological Survey — Geologic Investigation Series, Tempe Quadrangle
