The Barry/Baker tunnel on Bunker Road will be closed for maintenance during the weeks of 6/2 and 6/9. The tunnel will be open on the weekends. Please use Conzelman Road instead. More »
Muir Beach Overlook closure
The Muir Beach Overlook will be closed for Accessibility improvements and trail upgrades from June 2 through July 21. Alternate viewpoints are available along Highway 1 between there and Stinson Beach.
Rocks on the Move at Point Bonita
NPS Suzanne Garcia
Rocks on the Move at Point Bonita, Keepers of the Light and Land brings students to the Point Bonita Lighthouse trail, a location with both maritime and geologic significance. The high cliffs and volcanic rocks form a dramatic backdrop for students to work collaboratively to produce a simplified version of F. Leslie Ransome's 1893 geologic map of Point Bonita. Students work in teams to answer their questions about the changing landscape of an investigation site of their choosing.
By the end of the program, students have the opportunity to recognize evidence of weathering and erosion on Franciscan Complex rocks, and to consider the reasons why some of the Point Bonita pillow lavas remain essentially unchanged since the 1870s, while other sections of the trail erode and slide frequently. Students speculate on how the continued processes of weathering, erosion, human activity and climate change may impact the Point Bonita landscape in the future, and how these same processes impact their communities.
Click on the buttons on the right side of this page to take a virtual tour of the Point Bonita trail, and to see the geologic investigation sites.
To learn more about the Rocks on the Move experience at Point Bonita, view our annotated curriculum guide, with links to lesson plans and activities.
Did You Know?
Graywacke sandstone is a common rock at Golden Gate and was deposited on the deep sea floor by underwater landslides called turbidites.