Best National Reserve Concord Near Me

4worldlovers: Historically a shifting riverine sand dune ecosystem, the Antioch Dunes National Wildlife Refuge supports the last known populations of the endangered Antioch Dunes evening primrose, the Contra Costa wallflower, and the Lange's metalmark butterfly.

Due to the sensitive nature of the habitat, the refuge is closed to the public. However, our docent-led tours are back. See below for details.

The refuge was established in 1980 to protect plants and insects federally listed as endangered: Lange's metalmark butterfly (Apodemia mormo langei), Contra Costa wallflower (Erysimum capitatum var. capitatum), and Antioch Dunes evening primrose (Oenothera deltoides var. howellii). The refuge is the only known location in the world where the Lange's metalmark butterfly is found. Once part of an extended riverine sand dune ecosystem, the dunes of the refuge hosted a variety of endemic plants and insects. During the last 150 years, the dune ecosystem was seriously degraded by sand mining (removal), invasive plants, and other threats. Today, the refuge represents one of the last remaining riverine sand dune environments in the Sacramento–San Joaquin Delta.


Time to get outside again and enjoy a stroll through the dunes.


Our knowledgeable and fun docents lead a free 1-1.5-hour tour through the dunes every second Saturday of the month throughout the year.


Many spring flowers are in full bloom, including the magnificent endangered species, Antioch Dunes Evening Primrose. No registration necessary.

Every second Saturday of the month at 10:00 a.m. throughout the year.

4worldlovers: No parking for school buses or chartered buses. Drop-offs and onboarding only.

Skyline Trail is closed between Fish Ranch Rd and Old Tunnel Road staging area due to a mudslide. View Map. Updated July 08, 2023.

The Wilcox Station Staging Area and McCosker Loop Trail will be closed for construction, from June 2020 to Spring 2023, for creek restoration and public access enhancements. The project restores over 3,000 feet of creek habitat, including daylighting 2,800 feet, previously culverted underground.

Cattle grazing has been part of the ecosystem in the East Bay hills since the 1800s and in Sibley for many decades and part of the East Bay’s ecosystem for many tens of thousands of years. Grazing is important to removing hazardous vegetation to reduce wildfire risks and maintaining and improving natural habitat for plants and wildlife.

If cattle are blocking the trail, approach slowly, speak normally, and allow them to move away.

Cows are protective of their calves. Do not try to get close, touch, or pet them.

East Bay residents have a volcano in their backyard at Sibley Volcanic Regional Preserve. Originally called Round Top Park, Sibley shares with Temescal and Tilden the distinction of being one of the East Bay Regional Park District's original parks. The preserve was later named in honor of Robert Sibley, who helped found the District and served for 10 years on its board of directors.

Round Top Road is paved to the top of Round Top. (Watch for occasional vehicles using the road.) There is also a 600-foot, paved wheelchair path north of the visitor center that ends at a viewing platform. Quarry Road, beginning at Old Tunnel Road, is also paved.

Round Top (elevation 1763 ft. above sea level) is the preserve's most prominent feature.

The unstaffed visitor center at the Skyline Boulevard staging area has displays illustrating the preserve's geology. A self-guided brochure is available at the staging area highlighting the preserve's geological features.

Several trails provide access throughout the preserve. The 31-mile East Bay Skyline National Recreation Trail, part of the Bay Area Ridge Trail system, traverses the preserve along the ridgeline between Wildcat Canyon and Anthony Chabot Parks. Round Top Road goes from the Sibley visitor center to the top of Round Top. Round Top Loop Trail circles Round Top peak. Volcanic Trail, once a quarry haul road, contains most of the stops on the self-guided volcanic tour.

From Old Tunnel Road on the northwest side of the park, the paved Quarry Road ascends and meets the east end of Volcanic Trail. Quarry Trail connects the middle of Volcanic Trail to a point lower down on Quarry Road. Finally, Pond Trail is a short trail segment that descends to a couple of ponds on the north side of the preserve.

Most trails are hiking and equestrian only. A few trails are multi-use. Dogs are permitted at Sibley, but are not allowed on adjacent Huckleberry trails. A visitor center at the park shelves self-guided tour brochures so guests can stroll the park and learn of its historic significance at their own leisure.

Bicycles are not allowed on narrow-gauge trails, except on the Skyline Trail between the Sibley visitor center and Old Tunnel Road. Bicycles are allowed on the wider-gauge fire trails and paved roads, but are not allowed on Round Top Road from the fork .15 mile east of the visitor center to the top of Round Top.

Round Top, one of the area's highest peaks, is made up of lava and volcanic debris left over from a 10-million-year-old volcano. During the past 10 million years, massive tectonic forces on the Hayward and Moraga earthquake faults uplifted the Berkeley hills, folding bedrock formations and tilting the Round Top volcano complex on its side.

Softer sedimentary rock from the Orinda Formation eroded away, exposing the Round Top volcano. In addition, quarrying in the north half of the preserve has revealed cross sections of the bedrock geology, providing an unsurpassed outdoor laboratory for studying volcanism in the Central Coast Ranges.