Given Arizona’s rich Native American history, the state is riddled with ancient rock art. Many of these mysterious symbols provide information about the tribes that drew them, from what they ate to religious beliefs and everything in between. This particular cluster of petroglyphs, however, tells us little about the people who created them, due not only to them vanishing into thin air but also because the drawings served a much different purpose.

Located in Saguaro National Park West, Signal Hill is a 0.3-mile hiking trail suitable for all fitness levels. In addition to the thousands of majestic cacti that guard our desert landscape, the path also features mysterious symbols drawn over 1,000 years ago.

Flickr/Jim Roth

As spring arrives, wildflowers begin to bloom along the trail, adding vibrant pops of color to the scenery. The Signal Hill trail is a popular spot from March through November, but our favorite time to visit is early spring, as the temperature remains mild and comfortable.

Flickr/mytravelphotos

You’ll come upon several structures built by the Civilian Conservation Corps nearly 100 years ago. Though incomparable in age to the hike’s main attraction, these incredible historic relics are surprisingly well-preserved.

Flickr/mytravelphotos

Jim Roth/Flickr Now, onto the main feature - these ancient drawings were etched into the rock faces by the Hohokam people, who mysteriously vanished without a trace during the 15th century.

Archaeologists have spent decades trying to decipher the art, but it was a photographer who finally cracked the code. Rather than a bunch of pictures providing information about the tribe, Signal Hill is actually one of the most elaborate sundials discovered to date.

Flickr/hockeyholic

Viewers with no knowledge of these age-old timepieces see symbols randomly scattered across the boulders. Closer examination, however, reveals that solar events such as equinoxes and solstices cause light beams to pierce the drawings like arrows.

Flickr/ginsnob

This particular carving is on a rock tilted to 32 degrees, which is the latitude of Saguaro National Park. When a small rock is placed in the center, it creates a shadow that keeps track of seasons and upcoming equinoxes. The rock’s shadow also disappears at noon - an even more convincing piece of evidence that a sundial is, in fact, at work here.

Flickr/hockeyholic

As the petroglyph site at Signal Hill is a bit off the beaten path, the National Parks Service recommends against using a map app to find them. You can find driving directions to Saguaro National Park West and further information on the NPS website here.

Loren Shelton/Google

Have you ever seen these ancient symbols at Signal Hill? Where are your favorite petroglyphs in Arizona? We think this place is pretty neat: This Funky Little Town In Arizona Is A True Hidden Gem.

Flickr/Jim Roth

Flickr/mytravelphotos

Jim Roth/Flickr

Now, onto the main feature - these ancient drawings were etched into the rock faces by the Hohokam people, who mysteriously vanished without a trace during the 15th century.

Flickr/hockeyholic

Flickr/ginsnob

Loren Shelton/Google

OnlyInYourState may earn compensation through affiliate links in this article.