Pilot Knob, Volcanic summit near Yuma, California, US

Pilot Knob is a volcanic plug rising 876 feet (267 m) west of Yuma, Arizona, in Imperial County, California. The entire mountain block spans about 2 by 2 miles, and a rock quarry on its north side is visible from Interstate 8. The All American Canal cuts along its south border.

The formation was documented in 1774 by Juan Bautista de Anza during his regional exploration and recognized as a navigation point. It served riverboat traffic on the Colorado River as a critical landmark throughout the 1800s and into the early 1900s.

Pilot Knob bore several names: the Quechan knew it as Avie Quah-la-Altwa and Ha-bee-co-la-la, and Spanish maps called it San Pablo after Anza's 1774 naming. The Butterfield Overland Mail placed Pilot Knob Station near the river and the peak in 1858, and the name Pilot Knob itself comes from its use as a steering landmark for Colorado River boatmen.

The area is managed by the Bureau of Land Management and offers a campground at the base of the peak. Access is straightforward through Interstate 8, making it easy to reach the site for visitors exploring the region.

From the 1950s through the 1970s, the peak housed broadcasting equipment that transmitted television and radio signals across the region. The remnants of this communications infrastructure can still be spotted by visitors exploring the summit.