Since it first opened in 1776 as a Spanish Army post overlooking San Francisco Bay, the Presidio has made a slow and steady transformation back to its original state as an epic natural green space in The City, and has been part of the National Park Service since 1994.

Today our 1,491-acre, urban national park continues its ongoing evolution with the opening of a brand new trail, cutting through the area's $23 million wetlands restoration project set in the foreground of the Golden Gate Bridge. And, with socially distanced outdoor strolls among the few activities allowed to Bay Areans under the new stay-at-home order, we can't think of a better time to get out and explore new terrain.

As of Friday, the Quartermaster Reach Marsh is accessible to locals with seven acres of tidal marsh land along the Presidio's northern shoreline near Crissy Field. Once unreachable and unkempt, the old "Army-era landfill" has been restored to a wetland landscape, crisscrossed with creeks and corridors where flora and fauna can meet Bay Area nature lovers.

"Work at Quartermaster Reach Marsh brought an 850-foot length of the stream once buried in a pipe back above ground through excavation," said Lisa Petrie of the nonprofit Presidio Trust. "The Presidio Trust Box culverts were then installed beneath Mason Street at Crissy Marsh to allow the freshwater of the stream to flow into the saltwater marsh and San Francisco Bay, creating a unique brackish habitat that is vital to a variety of plant and animal species."'

Planning for the project has been 10 years in the making, beginning with the seismic retrofitting of Doyle Drive, which became Presidio Parkway. The restoration of the marsh also represents a milestone in the 20-plus-year revitalization of the Tennessee Hollow Watershed, the largest of its kind in Presidio that also flows through the new marshland.

"When the Parkway was complete in 2015, there was still a long process of transferring the project to the Presidio, cleaning things up underneath, and creating the conditions ripe for a natural marsh to thrive," Petrie adds, noting that the project team is currently planting some 23,000 salt marsh and dune plants of more than 40 different species of plants, all grown in the nearby Presidio Nursery, to create an attractive habitat for migrating shorebirds and water animals including the increasingly rare Olympia oysters, the only oyster native to North America's West Coast.

"The new trail

As far as hiking is concerned, San Franciscans can look forward to a new route called the Tennessee Hollow Watershed Walk, a network of paths that includes a pedestrian bridge and a quarter-mile trail section to the Tennessee Hollow Trail, "linking the interior part of the Presidio's watershed to Crissy Field and the Bay for the first time," said Petrie.

The trail, too, will create more birding spots to observe native avian fauna like killdeer, herons, and coots, which have already taken up residences in the marsh.

While the plants are in their sapling phase, the site still feels somewhat bare but you can, of course, expect excellent views of the Golden Gate Bridge, Alcatraz and Crissy Marsh.

// For more information on the Quartermaster Reach Marsh, visit presidio.gov.