Starting Monday, a 750-foot stretch of Panoramic Highway will be reduced to one lane for construction of a retaining wall. A temporary traffic signal will be in operation to allow alternating two-way access. A Mount Tamalpais State Park trail downhill of the work zone will also be closed during construction work hours.  

People traveling between the Mount Tamalpais area and Stinson Beach areas should expect traffic delays of up to 10 minutes, according to a Marin County press release published on Thursday.  

The stretch of road is about 1.3 miles northwest of the Four Corners intersection — where Panoramic Highway, Sequoia Valley Road, and Muir Woods Road meet, just south of the Mountain Home Inn, at milepost 2.26. The stretch of road is on a popular route for tourists visiting Mount Tamalpais State Park, Muir Wood National Monument, the Golden Gate National Recreation Area, Point Reyes National Seashore and Marin’s Pacific beaches, according to the press release. 

This construction is part of a slide repair project aimed at repairing damage from an October 2021 storm, when the area experienced 12 inches of rain within a 24-hour period, The project, managed by the Marin County Department of Public Works, aims to install new retaining walls, guardrails, and pavement along Panoramic Highway, according to a Marin County press release. The project began in November of 2023.  

Stinson Beach is seen from Mount Tamalpais State Park in this 2019 image. (Photo courtesy Alan Grinberg/Flickr)

The closed Mount Tamalpais State Park trail downhill of the work zone, Panoramic Trail, will be marked with signage by park employees, including recommended detours.  

One hiking trail within Mount Tamalpais State Park, called Panoramic Trail, is downhill of the work zone and will be closed during construction work hours. Park personnel plan to add signage about the trail closure and recommended detours. 

Construction is expected to end in March, but may go longer, according to a Marin County press release published on Thursday. It is one of 13 construction sites planned for the coming months, funded by the Highway Safety Improvement Program and the Federal Highway Administration Emergency Relief program. 4,500 feet of older guard railings are set to be replaced in West Marin.  

Expedited access will still be provided for active emergency service vehicles.