A Complete History Guide for Mt. Lemmon, Arizona and the small town of Summerhaven
Mt. Lemmon, tallest peak in the Santa Catalina Sky Island, has a unique history. Few people realize what a special place Mt. Lemmon is, aside from the allure of a cool summer escape. From ancient paleo-Indians 4,000 years ago, to the complex Hohokam culture a thousand years ago, to the Spaniards of the 1542 Coronado Expedition, to the Apaches and 19th century Mexican and Anglo-American pioneers of Arizona’s Territorial Period, to the residents of a 21st century metropolis, Mt. Lemmon (9,159′) and the Catalina Mountains on Tucson’s northern periphery have been exploited and enjoyed by many peoples seeking woodland resources and a respite from the scorching desert floor. Long before European settlement, the Tohono O’odham people—Indigenous to the region—called the peaks Babad Do’ag, meaning “Frog Mountain.” The Catalinas were, and remain, significant for their cultural, spiritual, and resource value to Indigenous communities.
Sara Allen Plummer Lemmon never got the credit she deserved for the decades of research she conducted with her botanist husband, but she did receive the ultimate recognition for her work in Southern Arizona. In the early 1880s a mountain was named in her honor.
Sara was an equal partner in collecting and researching plant specimens, yet in the scientific papers and articles published by her husband, credit is given to “J.G. Lemmon & Wife.”
“We will perhaps never know how much of the Lemmons’ joint work was her doing, but we might suspect that it was considerable,” wrote Frank S. Crosswhite in a 1979 article for the University of Arizona-produced journal Desert Plants.
Sara Plummer was born in Maine. Most accounts give 1840 as the year of her birth, however, the marker on her Northern California grave indicates she was born four years earlier. She attended college in Massachusetts before taking a job teaching art in New York. However, a bout of pneumonia during a New York winter prompted her to move to seek out a more temperate climate on the West Coast. Plummer, an accomplished artist and a published writer, was considered “one of the first ‘intellectuals’ to come to Santa Barbara,” according to newspaper accounts.
Her vigor restored by the warm ocean breezes, Plummer took long walks on the beach, in the foothills and up mountain slopes where her interest in plants was cultivated.
Plummer started the first library in the seaside town. She charged readers 10 cents to check out books and sold art supplies and knick knacks to make money.
Sara Lemmon with her husband. Photo courtesy of the Arizona Daily Star
She met John Gill Lemmon in 1874 when the noted botanist came to town for a speaking engagement. Lemmon, who preferred to go by his initials, J.G., was born in Michigan in 1832. After attending Michigan State, he became superintendent of county schools. However, his enlistment in the Fourth Michigan Cavalry in 1862 changed the course of his life. Lemmon never fully recovered from his capture by Confederate soldiers and his 15-month incarceration in a notorious Georgia prison. He emerged “an emaciated feeble survivor of Andersonville atrocities and after a year of liberal diet weighed finally a whole 90 pounds.”
Lemmon convalesced at his brother’s home in Sierraville, Calif. As he regained his strength and began roaming the desert, the war vet became interested in plants he had never before seen.
Six years after their first meeting, J.G. and Sara wed. It was at Sara’s urging that the couple embarked on an extended honeymoon to Southern Arizona. They called it their “botanical wedding trip.”
The intrepid Lemmons set out on their own, camping in a rustic “stick and mud cabin” at the base of the Catalinas before upgrading to a cave. According to a 1905 article in the Tucson Citizen: “Mrs. Lemmon … was not alarmed in the least at the prospect of danger. She rather invited it. She was fond of adventure and in the 25 years during which she and her husband have explored the slope mountains they have had their share of excitement.”
The couple approached the Catalinas from the south, but even with their ample planning, the mountains proved impossible to conquer.
After three failed attempts to scale the mountains, the couple returned to Tucson – the southern ascent was not without its rewards: They had discovered dozens of new species that today carry the name lemmoni.
It was with their approach from the north side of the Catalinas that the Lemmons found success.
After a 40-mile coach ride to Oracle, they loaded their equipment onto a pack mule and headed into the foothills. Sara scaled the primitive trails on foot while an ailing J.G. rode the mule. At Pandora Ranch, they found owner E.O. Stratton willing to take them to the summit.
Stratton was a college-educated New Yorker turned frontiersman. He guided the Lemmons, on horseback, up the mountain, where they found lodging at a homestead in what today is Summerhaven.
“The Lemmons and I went to the highest peak in the Santa Catalinas and christened it Mount Lemmon in honor of Mrs. Lemmon, who was the first white woman up there,” recounted Stratton in the book “Pioneering in Arizona: The Reminiscences of Emerson Oliver Stratton & Edith Stratton Kitt.”
After the Lemmons’ two-year expedition in Southern Arizona, which included forays into the Huachuca Mountains to catalog more new plant species, they returned to California to continue their work.
Despite research trips that spanned from Mexico to Alaska, it was Arizona that beckoned. For their 25th wedding anniversary, the Lemmons returned to Tucson to once again retrace their steps – accompanied by Stratton – up the 9,157-foot peak which had, by then, been officially designated Mount Lemmon.
Scientific Exploration and Ecology
The Lemmons were part of a wave of 19th-century naturalists exploring the American Southwest after the Civil War. They documented hundreds of plant species, expanding scientific understanding of the region’s unique biozones—from desert flora at low elevations to coniferous forests near the summit.
The mountain’s dramatic elevational change creates distinct ecological zones, making it a valuable site for ongoing biological, botanical, and ecological research. Today, climbers and scientists alike continue to study its biodiversity.
Road Construction and Early Development
Through the early 20th century, Mount Lemmon was remote and difficult to reach. Mining activity in the Santa Catalinas—particularly copper, gold, and silver claims in the early 1900s—highlighted the need for improved access, but rugged terrain made travel arduous.
In the 1920s and 1930s, local residents and civic groups began raising funds for a road. Fundraisers such as horned toad races in 1929 helped support early construction efforts.
The major breakthrough came when construction of the Mount Lemmon Highway (also called Catalina Highway or General Hitchcock Highway) began in 1933, largely using labor from a nearby Federal Prison Camp. The scenic road, winding from the desert floor to alpine conditions, was completed in 1950–1951. This connection transformed the mountain into a regional destination for tourism, recreation, and scientific facilities.
Photo courtesy of the Coronado National Forest
The community of Summerhaven developed along the upper portions of the highway as a seasonal and year-round settlement. Early hotels, cabins and tourist facilities emerged there in the mid-20th century—including the Mount Lemmon Inn (opened 1945) and other key hotels. Fires in 1977 and again during the Aspen Fire of 2003 destroyed several historic buildings, reshaping the built environment but not diminishing the village’s attraction.
Summerhaven remains the social and logistical hub on the mountain with cabins, shops and eateries that cater to visitors from Tucson and beyond.
Recreation: Skiing, Climbing, and Tourism
Despite Arizona’s desert reputation, Mount Lemmon’s high elevation supports substantial snowfall in winter. This led to the establishment of the Mount Lemmon Ski Valley, one of the southernmost ski areas in continental U.S. Skiing began in the mid-20th century as local clubs promoted winter recreation, and over time the resort grew into a year-round attraction with chairlifts that operate for scenic summer rides as well as winter skiing.
Climbing, mountain biking, and hiking routes on Mount Lemmon are world-class and range from desert foothill trails to high-alpine ridgelines. The mountain’s varied terrain draws outdoor enthusiasts throughout the year.
Cold War & Astronomy
From 1956 to 1969, the summit hosted the Mount Lemmon Air Force Station, a radar installation that was part of the U.S. Air Defense Command during the Cold War. It monitored airspace for potential threats and housed radar equipment and support facilities at high altitude. The military installation was a high-altitude Cold War radar site at 9,150 feet used by the 684th Aircraft Control and Warning Squadron to monitor for Soviet bombers. It was considered the “world’s highest continuously operated radar station” during its time.
After military decommissioning, astronomy became a defining scientific use of the site. The Mount Lemmon Observatory and later the Catalina Sky Survey leveraged the clear southern skies for research—especially in discovering comets and tracking near-Earth objects. Public-oriented programs like the SkyCenter further expanded astronomical outreach and education.
Modern Legacy
Today Mount Lemmon symbolizes both natural wonder and cultural history. It blends Indigenous heritage and scientific exploration with outdoor recreation and scenic beauty. The Catalina Highway has been designated a National Scenic Byway—the Sky Island Parkway—celebrating the dramatic transition from desert to woodland in a short geographic span.
The mountain hosts events like the Mount Lemmon Marathon series and continues to inspire adventurers, scientists, and everyday visitors drawn to its unique high-desert environment.