In about nine weeks, mountain lions, bobcats, coyotes and deer in Southern California will get something they’ve never had: a safe way across one of the region’s busiest freeways.
The Wallis Annenberg Wildlife Crossing over U.S. Route 101 in Agoura Hills is set to open December 2, 2026. When it does, it will be the largest wildlife crossing in the world. And here’s the part that should make any self-reliant reader smile: most of the money to build it came from private donors, not taxpayers.
A Bridge for Animals, Not Cars
The crossing sits near the Liberty Canyon Road exit, where more than 300,000 vehicles pass every day, according to the project’s official website. It spans all ten lanes of the 101, plus the neighboring Agoura Road.
The numbers are big. The main structure over the freeway is 250 feet by 174 feet. A second piece over Agoura Road adds another 71 feet by 175 feet. Together they cover about 55,925 square feet, the project says.
Builders poured 26 million pounds of concrete, according to FOX 11 Los Angeles. On top sits about an acre of habitat planted with 5,000 native plants. An Indigenous-led nursery team hand-collected more than 1.1 million local seeds to grow the plantings, FOX 11 reported. The goal is for animals to feel like they’re walking through the hills, not over a highway.
The $92 million Wallis Annenberg Wildlife Crossing in Agoura Hills appears to have a long way to go, but the California Natural Resources Agency is still confident it will open on time in ten weeks. https://t.co/SdRxzJrMgd pic.twitter.com/Ko8YBSZxDw
— California Post (@californiapost) September 24, 2026
People won’t be allowed on the crossing itself, but a public viewing platform will let visitors watch it work.
Paid for by Donors
According to the project’s FAQ, the estimated total cost as of 2025 was about $114 million. (A recent news report put the figure at $92 million, so estimates vary.) More than $100 million came from private donations from over 6,000 donors worldwide.
The largest gift was $26 million from philanthropist Wallis Annenberg and the Annenberg Foundation. Federal funding amounted to $2.5 million, and the remaining public money came from sources set aside for conservation. The project says no transportation dollars were diverted to build it.
That is a model worth noticing. When people care about something, they can pull together and pay for it themselves.
The Mountain Lion Who Started It All
The crossing grew out of the story of P-22, a mountain lion who survived perilous freeway crossings to settle in Griffith Park, in the middle of Los Angeles. He died in December 2022, but he remains a local legend.
Mongabay this week revisited the famous photo of P-22 walking beneath the Hollywood sign at night. Photographer Steve Winter spent 15 months trying to get the shot, battling stolen cameras and failed equipment along the way. A National Park Service biologist, Jeff Sikich, first thought Winter was “crazy” because he didn’t believe any mountain lions lived in the park. The image became a symbol of the campaign for the crossing.
Why It Matters
Freeways have boxed in the mountain lions of the Santa Monica Mountains. Unable to roam and find new mates, they have developed what the project calls “among the lowest genetic diversity of any mountain lion population ever documented.”
The crossing is meant to reconnect habitat that the freeway has split in two. It will also help bobcats, coyotes, deer, birds, reptiles and amphibians move more freely, according to the project.
Racing the Calendar
The project has been a long haul. Crews broke ground on Earth Day, April 22, 2022. The work now underway is the final stage, which includes the crossing over Agoura Road, utility relocations, earthwork and habitat restoration.
A September 24 report noted the site still looked like an active construction zone with about ten weeks to go. The project was originally supposed to wrap up in 2025, but record rains and flooding in back-to-back springs disrupted the schedule, officials said.
Still, the state is holding firm. “December 2nd remains the date when the Annenberg Wildlife Crossing will be ready for wildlife to cross,” the California Natural Resources Agency said, according to the report. Some planting and finishing work will continue after opening.
Want to Go?
A ribbon-cutting and public P-22 Legacy Celebration are planned for December 2 at King Gillette Ranch. If you’re traveling the 101 through Agoura Hills this fall, keep an eye out; you’ll be driving under the world’s largest animal bridge.
It’s a reminder that big things still get built in America when people decide they matter, and that conservation and private generosity can go hand in hand.
Sources
- 101 Wildlife Crossing: Crossing FAQ
- FOX 11 Los Angeles: World’s largest wildlife crossing sets opening date
- Mongabay: The mountain lion photo that helped change Los Angeles
- NewsBeep: LA’s Annenberg Wildlife Crossing looks unready for December opening