South Mountain Park stretches across more than 16,000 acres, making it one of the largest municipal parks in the United States. On any given weekend, hikers, mountain bikers, and families spread out across miles of desert trails.

But South Mountain did not begin as a protected outdoor playground.

There was a time when its future looked far less certain.

Long before trail maps and summit selfies, the South Mountains were used for grazing and small scale mining. Ranchers moved livestock across the desert foothills, and prospectors explored portions of the range. The land was rugged and largely undeveloped, but that did not mean it was guaranteed to remain that way.

In the early 1900s, Phoenix was still small, but it was growing. As the city expanded, flat farmland was the first to be developed. The mountains, at least initially, were considered less practical for housing. That bought South Mountain time.

But time alone does not protect land.

The turning point came during the Great Depression. In the 1930s, the Civilian Conservation Corps arrived in Arizona as part of a nationwide public works effort. Crews were assigned to develop infrastructure in what would become South Mountain Park.

They built roads. They constructed stone retaining walls. They created lookout points, including what is now known as Dobbins Lookout. Many of the stone structures hikers see today were built by hand during that era.

That investment did more than create scenic viewpoints. It established the land as a public park. Once designated and improved for recreation, the argument for preservation became much stronger.

Without that early commitment, portions of the range could have been parceled and sold as Phoenix expanded southward.

After World War II, Phoenix entered a period of explosive growth. Subdivisions spread across the Valley floor. Development pressed toward the edges of the city in every direction.

Because South Mountain had already been designated and developed as a municipal park, it had a layer of protection that other desert foothills did not. That status helped shield it from being gradually absorbed into surrounding neighborhoods.

Had preservation come later, the story might have been very different. The lower slopes could have been carved into housing tracts. Roadways might have cut deeper into the range. Access to the summits could have been fragmented or limited.

Instead, the park remained intact and continued to expand.

When you hike South Mountain, you are not just walking through open desert. You are walking through layers of history. Ranching routes. Early mining attempts. Depression era craftsmanship. Decades of civic decision making.

The scale of South Mountain Park today feels inevitable. It is not.

It exists in its current form because leaders and residents chose to establish and maintain it as public land before development pressure made that impossible.

From the summit views at Dobbins to the quiet washes along the National Trail, South Mountain stands as a reminder that open space in a growing city requires intention.

Phoenix could have chosen rooftops.

Instead, it chose ridgelines.