The Sky Islands

The Sky Islands sit at a great biological crossroads. Here the Rocky Mountains reach down from the north and the Sierra Madre of Mexico reaches up from the south, while the Sonoran Desert to the west meets the Chihuahuan Desert to the east. Plants and animals from all four of those worlds overlap in these mountains, which is why a birder can find both a northern species and a tropical one on the same slope. Scientists count the region among the most biologically diverse in North America.

Each mountain range is its own separate refuge. When the climate warmed after the last ice age, cool-weather forests survived only by retreating up the mountains, where the air stayed cold enough, and the desert closed in around their feet. The creatures stranded on each peak have been evolving in isolation ever since, which is how these small ranges came to hold species and even subspecies found on one mountain and no other.

The most vivid way to feel the Sky Islands is to drive or hike from bottom to top. You start among saguaro cactus and creosote in the Sonoran Desert, climb into rolling grassland, then into oak woodland dotted with the region's distinctive evergreen oaks. Higher still the oaks give way to tall ponderosa pine, and near the summits of the highest ranges you reach cool forests of Douglas fir, spruce, and quaking aspen that would look at home in the northern Rockies.

Naturalists describe this as passing through a stack of life zones, and the rule of thumb is that climbing a thousand feet in these mountains is roughly like traveling hundreds of miles north. On the tallest ranges, a summer visitor can leave a hundred-degree desert in the morning and be walking in cool pine shade with a jacket on by midday, which is exactly why generations of Tucson and southern Arizona families have escaped up into these mountains through the hot months.

People have lived among and looked to these mountains for thousands of years. The Tohono O'odham and their ancestors have long known this desert and its ranges, and the Apache made the rugged high country of ranges like the Chiricahua and the Dragoons their strongholds through the hard years of the nineteenth century. The leaders Cochise and Geronimo are bound to this landscape, and Apache people remain part of Arizona today.

The Spanish left their mark as well, and the whole national forest that protects much of this high country carries the name Coronado, for the sixteenth-century expedition that passed through this borderland in search of legendary cities of gold. Later came miners, ranchers, and the outposts of the frontier army, but the mountains themselves have always dwarfed the human story played out at their feet.

The Sky Islands are famous among birders, who travel from around the world to canyons like Ramsey and Madera in hopes of tropical species that reach the United States almost nowhere else, including a remarkable variety of hummingbirds and, in a few canyons, the flame-colored elegant trogon. The forests and grasslands also hold black bear, mountain lion, white-tailed and mule deer, coatis, and a returning population of the region's native wildlife.

Each season shows the mountains differently. Spring and early summer are dry and warming, with wildflowers moving up the slopes. The summer monsoon brings dramatic afternoon storms and a burst of green. Fall lights the aspens and canyon maples gold and red at elevation, and draws migrating birds through the canyons. Winter dusts the high peaks with snow while the desert below stays mild, so on a clear day you can look up from warm sunshine at a white mountain crown.

The closest Boutel™ stays, so you can turn this stop into an overnight. Each is a place we chose through independent editorial review, never a paid placement.

The Sky Islands are a remarkable series of isolated mountain ranges in southeastern Arizona and the surrounding region, where high, forested peaks rise dramatically from the surrounding seas of desert and grassland like islands in the sky. Because these cool, moist mountaintops are separated from one another by hot, dry lowlands, they harbor extraordinary biological diversity, including unique and rare plants and animals, and a blend of species from the Rocky Mountains, the Sierra Madre of Mexico, and the deserts. Ranges like the Chiricahuas, Huachucas, and Santa Ritas make the Sky Islands a world-renowned hotspot for nature and biodiversity.

The Sky Islands are exceptionally diverse because their isolated mountains sit at a crossroads of major ecological regions, mixing species from the Rocky Mountains, Mexico's Sierra Madre, and the Sonoran and Chihuahuan deserts, while the dramatic range of elevations creates many distinct habitats stacked from desert to pine forest. The lowland deserts isolate the cool mountaintops like islands, allowing unique populations to develop. This combination produces an astonishing variety of plants, birds, mammals, and other wildlife, including many rare and found-nowhere-else species, making the Sky Islands one of the most biodiverse regions in North America.

You can hike and explore the many mountain ranges, from the rock spires of the Chiricahuas to the birding canyons of the Huachucas, enjoy world-class birdwatching for rare species, drive scenic routes like the ascent of Mount Lemmon that climb through multiple life zones, camp, and take in the dramatic contrast of desert and forest. Wildlife viewing, photography, and nature study are major draws. With their spectacular scenery and unmatched biodiversity, the Sky Islands offer rich rewards for hikers, birders, and nature lovers exploring southeastern Arizona.

Spring through fall is generally best, with the higher elevations offering a cool escape from the summer desert heat and prime birding in late spring and summer, and fall bringing pleasant weather and color, while winter can bring snow to the peaks. Because the ranges span many elevations, conditions vary widely, so the mountaintops stay cool while the deserts below are hot. For birding and comfortable mountain exploration, the warm-weather months are ideal, though the varied elevations mean there is something rewarding in most seasons.

The Sky Islands of southeastern Arizona include ranges near Tucson, like the Santa Catalinas with Mount Lemmon and the Santa Ritas, and farther southeast the Huachucas near Sierra Vista with Ramsey Canyon and the Chiricahuas near Willcox with Chiricahua National Monument and Cave Creek Canyon. The Wild West and mining towns of Tombstone and Bisbee and the region's wine country lie among them. That makes the Sky Islands a spectacular natural framework to combine with the birding, history, and scenery of southeastern Arizona.