An elegant fix for one of America’s deadliest road problems

When the Wallis-Annenberg Wildlife Crossing opens in December, it will be the largest of its kind in the world. | Dean Musgrove/Los Angeles Daily News In 2012, Southern California was besotted with an unlikely celebrity: a telegenic mountain lion who had crossed one of the state’s most perilous freeways , seeking a territory to call his own.

Widely deemed “ LA’s loneliest lion ” and “ most eligible bachelor ,” the chiseled puma in question, named P-22, roamed the bustling but otherwise big cat-less Hollywood Hills, unable to safely return to the home he’d left behind.

His search for a mate below the Hollywood Sign rendered him an icon of his city, but also a rueful reminder of the sprawling highways that bifurcated his habitat in the first place, leaving his clan on the other side of I-405 on the verge of local extinction .

Beth Pratt, then recently named head of California’s branch of the National Wildlife Federation, remembers strolling through Griffith Park with the wildlife biologist Jeff Sikich in 2012.

Pratt knew that P-22 roamed somewhere nearby, and she found herself wondering aloud how she could help.

“Well, there’s this little wildlife corridor we need to get built,” Sikich told her.

“I’m like, ‘Sure, how hard can it be?’” she recalled to me with a laugh.

“Well, apparently, it’s quite hard.” Fourteen years later, the project they discussed that day, now known as the Wallis Annenberg Wildlife Crossing, is finally scheduled to open in December.

When it does, it will be the largest real-life animal crossing in the world, a gorgeous, vegetated overpass offering safe passage to local mountain lions, coyotes, deer, and black bears across the perilous 10-lane Ventura Freeway, where P-22 dodged cars back in 2012.

Though P-22 died before he could take advantage of that crossing himself, he helped engender a movement that, hard as it may have been to pull off in LA, could help revolutionize how animals cross America’s most dangerous roads, preventing some of the hundreds of human deaths , hundreds of millions of animal deaths , and billions in damages caused by wildlife collisions each year.

It is a species of elegant, bipartisan infrastructure that, if you squint, might even make you believe in America’s ability to build again, and to build in a way that still lends a hand — a paw, if you will — to the least empowered among us, a stranded salamander or the loneliest of lions.

As Pratt put it: “What’s more hopeful than rewilding one of the world’s busiest freeways?” Wildlife crossings used to be rare in the US.

Not anymore.

When Pratt first pitched the idea for a wildlife crossing across the 101, such projects were still rare in the US, and rarer still across such a major thoroughfare.