Marin County Parks and Open Space Department

The Marin County Open Space District (MCOSD) manages 250 miles of roads and trails on 34 open space preserves. Roads and trails may be temporarily closed, or use restricted, due to safety, wet weather, natural hazards, wildland fire, construction, or restoration. Please cooperate with closure signs and notices, and take alternate routes.

Project Impacts and Closures: Roads and Trails

Horse Hill Preserve

Horse Hill Trail work on the Horse Hill Trail project has been completed. The new segment of Horse Hill Trail is closed to equestrians until further notice. Soils on the new segment of Horse Hill Trail need time to settle and compact naturally. If conditions allow, the Marin County Open Space District (MCOSD) expects to reopen Horse Hill Trail for equestrian use during spring 2018. Gasline Trail will remain open to equestrians until Horse Hill Trail is ready for equestrian use. For safety, please observe posted trail closure signs.

Terra Linda/Sleepy Hollow Preserve

Irving Fire Road Work on the Irving Fire Road project has been completed. Marin County Parks began work on Irving Fire Road in Terra Linda/Sleepy Hollow Open Space Preserve in May 2017. This project will reduce sedimentation into the watershed and maintain safe emergency access. This project was funded by Measure A..

Seasonal Closures: Roads and Trails

Roads and trails may be closed during the rainy season, typically November through March, for visitor safety and natural resources protection.

Updated On:


We update this page when closures, openings, or conditions change.