Pilot Knob

Pilot Knob is an extinct volcano in Travis County, Texas. The formation consists of four rounded hills that together create a central area with a diameter of roughly two miles (three kilometers).

Around 80 million years ago, this volcano formed when magma met waterlogged sediments in a marine setting. The eruption left ash and rock that mixed with the marine deposits of this region.

The name refers to its function as a landmark for travelers passing through this area. Today hikers and cyclists often cross the terrain, following the same natural paths that once served as routes.

Visitors can observe volcanic deposits beneath limestone overhangs at the upper and lower falls in nearby McKinney Falls State Park. The trails in this area suit walking during dry weather, while the rock layers show best in good light.

This volcano ranks among the largest of the 75 former volcanoes in Texas. The basaltic rocks formed during the eruption enriched surrounding soils and improved conditions for farming.

Location: Travis County

GPS coordinates: 30.15876,-97.70810

Latest update: December 5, 2025 22:25