Discover the Napa Valley hike known mostly to locals

Waist-deep in a natural pool at Moore Creek Park in eastern Napa Valley, Gabby Gonzalez-McNamara arches back and closes her eyes, basking in sunlight filtering through a dense thicket of trees.

The 49-year-old Napa therapist holds the serene pose for a few seconds before plunging headfirst beneath the surface. Coming up for air, she shrieks in shocked delight.

“I love cold water!”

Gonzalez-McNamara worked up a drenching sweat on this Sunday afternoon, a few weeks before our recent rainy weather, after she and a friend hiked roughly 3 miles from the parking lot on Chiles Pope Valley Road to what is described on park maps as the “secret swimming hole.”

The pool, filled year-round with crisp, spring-fed water, is a unique attraction of this hidden gem of a park, which is only 10 miles from downtown St. Helena and yet feels worlds away from Wine Country hubbub. The park is about an hour’s drive from Santa Rosa.

At 1,600 acres, Moore Creek encompasses mountainous terrain and a diverse landscape of oak woodlands, Douglas fir and madrone forest, chaparral and grasslands. The park’s southwest flank skirts Lake Hennessey, which is the city of Napa’s largest local reservoir.

The ecosystem supports a wide range of plants and wildlife, including gray fox, coyote, mountain lions and the occasional black bear.

Visitors enjoy gorgeous vistas, lakeside strolling, balancing-act creek crossings and wildflower explosions in spring that rival almost any in the state. In late fall and winter, rain swells creeks and spawns waterfalls.

However, despite its prodigious size, the park remains largely unknown outside Napa Valley, and even to many who call the valley home.

Making their second foray at the park on this particular Sunday, the O’Brien family of San Francisco — Bob, 55; Stephanie, 52; and McCann, 13 — had the main Moore Creek trail virtually to themselves.

The family first discovered the park after putting the phrase “good long hikes near St. Helena” into an online search engine. Even their friends who live in St. Helena had no idea Moore Creek existed.

“They asked where I had taken such beautiful photos, and I said, ‘It’s right near your home,’” Stephanie O’Brien said.

As a frequent visitor, Gonzalez-McNamara spoke of the park in reverential terms. Her ex-husband, Billy McNamara, joined her on the jaunt to the swimming hole. The pair remain close friends.

“Just as we need to plug in our cellphones to recharge them, I recharge myself here,” said Gonzalez-McNamara, who was born and raised in Mexico City.

As a technical issue, cellphone service in Moore Creek Park is almost nonexistent. That adds to the off-the-grid charm, but also is something to keep in mind when planning a visit. There also isn’t any potable water or other services beyond a couple of portable restrooms in the main parking lot.

The park comprises the 700-acre Moore Creek unit, purchased by the Napa County Regional Park and Open Space District in 2008, and the 900-acre Hennessey unit, which encompasses watershed purchased by the city of Napa when it developed Conn Dam and Lake Hennessey in the 1940s.

Combined, the park has more than 20 miles of multiuse trails for hikers, runners, mountain bikers and equestrians. One of the most popular routes is a roughly 6-mile out-and-back jaunt heading north from the parking lot along Moore Creek to the natural pool.

More information and detailed maps are available at the Open Space District’s website, napaoutdoors.org/parks/moore-creek-park.

Leashed dogs are only permitted on the Hennessey side. The lake itself is strictly off-limits to all park visitors, however. Note also that the park is closed when the risk of wildfire results in red flag warnings. The Open Space District’s website updates conditions daily.

There are no fees to enjoy Moore Creek, a rarity among Bay Area parks of this magnitude. Park operations are supported by grants and donations, including an annual Napa County grant of about $1 million, according to Ryan Ayers, a spokesman for the Open Space District.

Visitors are encouraged to make a modest donation when they visit the park. Payment kiosks are located in the main parking lot.

From downtown Santa Rosa, the park is about an hour away heading east over the mountains toward Calistoga, and then south to the Highway 128 turnoff to Lake Hennessey. There are numerous restaurants, tasting rooms and other places to fill up along the way.

Enjoying a cold beer after a recent mountain bike ride at Moore Creek, 35-year-old John King of Santa Rosa had praise for the park’s well-designed and maintained trails, saying they are good for newer riders.

Park managers also are in the final stages of formally dedicating a nearly 10-mile multiuse trail linking Moore Creek with Pacific Union College in Angwin. That section, which will be another link in the Bay Area Ridge Trail, will offer adventurers like Gonzalez-McNamara yet more opportunity to enjoy and explore the area.

“It’s magical,” she said.