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Don Edwards San Francisco Bay National Wildlife Refuge (Fremont)

The Don Edwards San Francisco Bay National Wildlife Refuge, the first and largest urban national wildlife refuge in the United States, is just one piece of the larger San Francisco Bay National Wildlife Refuge Complex. Encompassing 30,000 acres, the Don Edwards refuge consists primarily of tidal marsh, salt ponds, mud flats, and seasonal wetlands. It provides habitat for nine species of federally listed threatened or endangered species, including the salt marsh harvest mouse, California clapper rail, and western snowy plover, and is home to 227 species of birds. As a safe haven for vast numbers of birds traveling the Pacific Flyway, it is a prime destination for bird watching.

Public entry points for visiting Don Edwards are at its headquarters at the refuge's north end in Fremont, and at Alviso, which is around the southern tip of San Francisco Bay. More than 30 miles of trails lead along sloughs and past salt ponds on San Francisco Bay that are being restored to a mix of habitats. Depending on the season and the stage of salt development, the water ranges in color from green to mauve. A visitor center in Fremont and the Environmental Education Center in Alviso provide information about the refuge and how to explore it.

At the Fremont location there’s an accessible fishing pier at the end of Marshlands Road; from there you can also pick up a section of the Bay Trail that crosses the approximately 1.5-mile Dumbarton Bridge to San Mateo County. From Marshlands Road you can also follow the Quarry Trail to Coyote Hills Regional Park via a bridge that crosses Highway 84.

Visitor center:
The small visitor center, which overlooks LaRiviere Marsh––named for environmentalist Florence LaRiviere, who played a pivotal role in establishing the refuge––has exhibits describing endangered species and migratory birds. Through multimedia exhibits you can learn about the refuge, the South Bay Salt Pond Restoration Project, and flora and fauna found at the refuge. Behind the center is a viewing area with a few interpretive panels and a large map of the refuge.

Trail/Pathway Details

Tidelands Trail

Trailhead: From the main parking lot past the visitor center, follow the sidewalk across the service road

Length: 2-4 total miles

Typical Width: 4 ft. & above

Typical Grade: Mostly level or gentle

Terrain: Moderately Firm


Before starting out on the trail, you can travel a short distance up a very steep service road to a platform with broad views of the marshlands, salt ponds, sloughs, and Bay. Farther uphill are more trails, but they have very steep grades. To begin your hike, from the service road travel a few hundred feet downhill to a trail junction and an accessible picnic area overlooking the marsh. Traffic noise from Highway 84 disturbs this otherwise peaceful setting. For the most accessible route, follow the Tidelands Trail to the right; a few signs with plant names have been placed along this short stretch before you reach a side trail to the Newark Slough Learning Center.

Continue following signs for the Tidelands Trail, then cross an accessible long wooden bridge over Newark Slough to the junction with Newark Slough Trail. Here an abandoned hunting lodge has interpretive panels. It’s often windy at this spot; sunglasses can help keep the blowing dust from getting in your eyes. At this junction the trail is named both Newark Slough and Tidelands. Traveling in either direction, the 5.2-mile Newark Slough levee loop trail follows the curving path of Newark Slough around salt ponds and tidal marshes; refuge staff advised me that sections of the loop are inaccessible due to overgrown vegetation and narrow dirt passages. I followed it to the left for .25 miles to another accessible wooden bridge, then traveled uphill and reconnected with the Tidelands Trail. Here you can turn left and follow the trail .25 miles back to the start, or do as I did and turn right to connect to the Harrier Spur Trail.

As the trail curves inland, noise dissipates, the East Bay hills come into view, and a cluster of seemingly out of place century plants cling to the hillside. In less than .3 miles you reach the Harrier Spur Trail, which the map says is accessible; the steep approach to it wasn’t encouraging, so I turned around and followed the signs for Tidelands Trail back to the start.


Trailhead: Visitor center parking lot

Length: 1-2 total miles

Typical Width: 4 ft. & above

Typical Grade: Level

Terrain: Moderately Firm

The ride was quite bumpy and grass was overgrown on the section heading north from the elevated boardwalk.

Obstacles: A step at the bridge is not passable in a motorized wheelchair.


Trail maps indicate that this trail is accessible, but a 6-inch threshold at a bridge at the southern end of the trail caused me to turn back. There are no Bay views; instead, you look out across LaRiviere Marsh, with signs of industry on the horizon. The trail may be more appealing in spring and fall, when more birds are present. If you do decide to visit, you will travel for less than a tenth of a mile over firm gravel to a 500-foot-long elevated boardwalk. At the end of the boardwalk, if you turn left the levee trail is rough terrain all the way to Highway 84, and traffic noise increases. Turn right and you will reach the inaccessible bridge within a few hundred feet.

Accessibility Details

The facilities listed below meet all of our access criteria unless otherwise noted.

Visitor Center: Accessible

Accessible Parking: Yes

At the visitor center and in the large lot just beyond it, and at the end of Marshlands Rd. by the fishing pier.

Accessible Restroom: Yes

Outside the visitor center. An accessible portable toilet is halfway out the fishing pier, and another is by the picnic tables and overlook at the start of the lower Tidelands Trail.

Accessible Picnic Tables: Yes

At the visitor center, the trail junction for the Learning Center and Tidelands Trail, and the Learning Center. Halfway along the boardwalk over Newark Slough, an area that juts out over the marsh has a few tables, and there is one past the second bridge crossing.
View overlooking Newark Slough Trail
View overlooking Newark Slough Trail (Bonnie Lewkowicz)

Features icon key

  • bicycling
  • boating
  • fishing
  • hiking
  • picnic
  • wildlife viewing

Additional Information

View Map  
Managing Agency: U.S. Fish & Wildlife Service
Address: 1 Marshlands Rd.
Phone: (510) 792-0222
Hours: Trails: Daily, 9 am-5 pm. Fremont visitor center: Tues.-Sun., 9 am-5 pm.
Fees: None
Dogs: Not allowed
Public Transportation: AC Transit
Useful Links: Trail map
Reviewed by Bonnie Lewkowicz, June 29, 2014
Access Norhtern California This web guide is a project of Access Northern California.  
California Coastal Conservancy Thanks to our partner the California Coastal Conservancy

DISCLAIMER: Although the information contained in this web-guide was believed to be correct at the time of publication, neither Access Northern California nor California Coastal Conservancy shall be held responsible or liable for any inaccuracies, errors, or omissions, nor for information that changes or becomes outdated. Neither Access Northern California nor California Coastal Conservancy assume any liability for any injury or damage arising out of, or in connection with, any use of this guide or the sites described in it.

Accessible Restrooms Icon looks like a women and men restroom signBeach Accessible
Wheelchairs Available
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