Pets allowed
Not Allowed
Elevation Gain
110.00 ft (33.53 m)
Trail type
2.20 mi (3.54 km)
Please respect the outdoors by practicing Leave No Trace. Learn more about how to apply the principles of Leave No Trace on your next outdoor adventure here.

Home to nearly 700 different species of animals, the Elkhorn Slough is an amazing place to catch a wide variety of wildlife in their natural habitat. Hiking the South Marsh Loop is a quick 2.2-mile journey through this diverse landscape, and it takes you along the shoreline for some close-up opportunities to see these animals in action. Bird watchers and photographers should definitely put this trail on their list.

South Marsh Loop is located inside the Elkhorn Slough National Estuarine Research Reserve. You are required to pay an entrance fee and brush your shoes before you hike any trails in the reserve. Sudden Oak Death is a plant borne disease that is prevalent in California and Oregon, and scrubbing your shoes helps stop the spread of this disease.

The trailhead starts from the visitor's center and cuts through an open meadow toward an old 1920s dairy farm. This farm is a nexus for the South Marsh as well as the Five Fingers and Upper Valley Loops. Heading left from the South Marsh trail marker, the path takes you down to the waterfront where you will find a boardwalk heading out into the water. This boardwalk and the nearby bridge are excellent spots for viewing, especially when the tide is out.

The next section of this trail has a few short and worthwhile detours. You have the option to head out to Hummingbird Island, a half-mile walk that takes you across the railroad tracks and near the main channel of the slough. You can also take the North Marsh Overlook Trail for some excellent view points. The rest of the hike follows the shoreline until it connects back to the dairy farm. From here, you can continue to explore the upper areas of the reserve by taking the Five Fingers Loop or return to the parking lot.


Logistics + Planning

Preferable season(s)




Parking Pass

General Day Use Fee


Great chance to get close to wildlife.


No water at trailhead.

Trailhead Elevation

10.00 ft (3.05 m)


Bird watching
Big vistas


Nearby Adventures

Elkhorn Slough National Estuarine Research Reserve
Gabilan + Southern Diablo Mountains, California
Elkhorn Slough National Estuarine Research Reserve


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