--
Arrowhead Pinnacles
The pinnacles formations overlook the Summit Valley south of Hesperia on the edge of the Mojave high desert. Gigantic boulders piled and strewn about interspersed with Coulter pines and manzanita.
- 
- 
- 
- 
- 
- 
- 
Aerial Photos
Pilot Rock
Around 70 to 100 million years ago, molten rock slowly cooled far beneath the Earth’s surface, hardening into granite. At the time, the land above was very different—thicker, higher, and untouched by the peaks we know today. Over millions of years, huge forces along fault lines, including the nearby San Andreas, began pushing the land upward. The granite, once buried under miles of rock, was brought closer to the surface.
Once exposed, the real sculpting began. Rain, wind, and the daily freeze-and-thaw of mountain weather chipped away at the weaker stone around them. Natural cracks in the granite helped break it apart, and as pressure lifted, the outer layers peeled away. Slowly, the softer rock vanished, leaving only the toughest granite standing.
What you see now—those sharp, jagged points—is the end result of a very long, patient process. It’s the kind of place where you can imagine ancient travelers stopping to get their bearings, just as hikers do today, with wide-open views stretching from the high desert to the heart of the San Bernardino range.