Bothin Marsh Preserve

The shoreline along Bothin Marsh Preserve provides recreation and natural beauty for residents and visitors in southern Marin. The marsh also provides habitat for unique plants and animals. With current sea level rise projections, this preserve will lose a significant amount of vital wetland habitat by 2030. The Mill Valley-Sausalito Multiuse Pathway, which runs through the marsh, will also be greatly affected by increased frequency and severity of flooding. As One Tam partners, the Marin County Open Space District and the Golden Gate National Parks Conservancy are working with scientists to assess existing conditions and potential future impacts from sea level rise related to climate change. Sea level rise adaptation designs are being developed to preserve the marsh and protect the pathway. Community feedback is welcome. Learn more about Evolving Shorelines.

• Sunrises and sunsets reflect beautifully on the surface of the 106-acre marsh.
• The Mill Valley-Sausalito Pathway and Charles F. McGlashan Pathway traverse and run alongside Bothin Marsh, connecting to sections of the Bay Trail.
• Dogs welcome on leash. Stay on roads and trails. 

• This tidal wetland is a small reminder of the vast salt marshes that once surrounded San Francisco Bay.
• The marsh serves more than 400 species of migratory birds traveling on the Pacific Flyway. Observe birds and wildlife quietly from a distance. Migrating birds are resting after their long flights.
• The preserve is home to the endangered salt marsh harvest mouse and Ridgeway's rail.
• Bothin Marsh is at the center of discussions about how climate change is affecting Marin coastlines.
• Check out the iNaturalist field guide. Add your own observations.

• Stay on roads and trails to preserve sensitive ecosystems and to avoid trespassing on private property.
• Dress appropriately for the weather. Trails can be muddy during the rainy season.
• Bring water.
• There are no restrooms at this location.
• Steer clear of poison oak.
• After an outing, check for ticks.

The most popular entry for Bothin Marsh is on the 800 block of Miller Avenue, Mill Valley. From Highway 101, take exit 445B west towards Mill Valley, turn right at Miller Avenue. MCOSD gate is on the right, across from Almonte Boulevard.

Street parking only. Please be respectful of local residents. Do not block streets, gates, or driveways.

• Golden Gate Highway and Transportation District
• Marin Transit Trip Planner
• Route from San Rafael Transit Center

You can also dial 511 to find out about transit options from your location.

• No smoking or fires.
• Weapons and hunting prohibited.
• Motorized vehicles prohibited. (Individuals with qualified disabilities may operate certain kinds of zero-emission mobility devices on some roads,multiuse trails, and certain other facilities.)
• Everyone must yield the right-of-way to horses. Bikes must also yield to pedestrians.
• No model airplanes, drones, or other self-propelled crafts.
• Permit required for commercial use and groups of more than 15 people.
• Dispose of waste property. Pack it out.
• All resources are protected.

DOGS

• Dogs may be off-leash on fire roads only if kept under voice control. Leash must always be readily available.
• Dogs are allowed on signed trails and must be leashed. Leash must not exceed 6 feet in length.
• Off-fire road and off-trail use prohibited.
• Individuals accompanying dogs are required to clean up and remove pet waste.
• A maximum of 3 dogs per person is allowed. No commercial dog walking permitted in this preserve.

BIKES

• Permitted on signed fire roads and trails designated for multiuse and hikers/bikes.
• Off-fire road and off-trail use prohibited.
• Speed limit is 15 mph or less. Must slow to 5 mph when passing others or around blind turns.
• Electric bicycles are not permitted.

HORSES

• Permitted on signed fire roads and trails designated for multiuse and hikers/horses.
• Off-fire road and off-trail use prohibited except when watering or resting the horse.

In an emergency, call 911. To report an incident or suspicious activity, call the Ranger Field Office at (415) 473-2816 or submit an Incident Report via online form.

Visitors are responsible for knowing and obeying all Marin County Open Space District (MCOSD) regulations. Citations will be issued for violations. Read the official regulations: Marin County Municipal Code Appendix A.

Call (415) 473-6387 for more information regarding allowable types and use of mobility devices for people with qualified disabilities.

The MCOSD is a special district pursuant to the California Public Resources Code. Marin County Parks oversees the management of the county parks system and provides public information on behalf of the MCOSD.