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Would you try to cross this highway?

A real photo of a wide highway with many lanes and cars.
Would you try to cross this highway?
2 · A real moment on the freeway

Why would a mountain lion risk this?

Because staying on one side forever creates a different kind of danger.

0 / 2 explored
A mountain lion standing on a freeway next to a car.
THERE IS NO GOOD OPTION.Keep crossing, and the lion moves into traffic. Run back, and it still cannot reach the habitat it needs. The freeway has turned normal wildlife movement into a trap.
WHY CROSS AT ALL?

Mountain lions need room to move.

A lion may need to travel far beyond its usual area to survive and reproduce.

FOODfind prey
TERRITORYfind space
MATESfind other lions
Choose what the lion should do.Tap one of the two big yellow buttons below. The consequence will appear here.
3 · Meet P-22

This was P-22.

A wild mountain lion who somehow made a home in Griffith Park—right in the middle of Los Angeles.
GRIFFITH PARK
HOLLYWOOD SIGN
LA WILDLIFE ICON
P-22 became a symbol of a bigger problem.His life showed how hard it can be for wildlife to move through a city cut up by freeways.
P-22, the famous Griffith Park mountain lion, photographed beneath the Hollywood Sign
P-22The mountain lion that made Los Angeles pay attention to wildlife connectivity.
4 · P-22's impossible journey

He had to get across Los Angeles.

To reach Griffith Park, P-22 likely crossed two enormous freeways: the 405 and the 101.

2 FREEWAYS · 1 LION
P-22'S LIKELY JOURNEY
Exact route unknown · P-22 was not collared yet
SANTA MONICAMOUNTAINS GRIFFITHPARK PACIFIC OCEAN San Fernando Valley West Los Angeles Hollywood Santa Monica Beverly Hills Santa Monica Pier Getty Center Universal Studios Hollywood Sign Griffith Observatory 405 101
Watch P-22 move across the map.
HE MADE IT—BUT HE WAS STILL ISOLATED.Griffith Park became P-22's home, but it was surrounded by roads and city. To researchers' knowledge, he never found a mate.
STARTSanta Monica Mountains
ENDGriffith Park
Illustration of a wildlife overpass with fencing guiding animals across the road while cars travel underneath.
A SAFER WAY EXISTS.

A wildlife crossing gives animals a safer way across.

P-22 survived crossing two major freeways. A wildlife crossing can help other animals avoid taking that same risk.

Animals cross above. Cars stay below.Fences help guide wildlife toward the crossing instead of onto the road.
6 · Build a piece of mountain

How do you turn a bridge into habitat?

The real Wallis Annenberg crossing did not become green all at once. It was built in layers.
A bridge is only the skeleton.Wildlife needs soil, native plants, shelter, darkness, and a landscape that feels connected to the mountains on both sides.
6
Follow the real construction. Tap the yellow button to move through the real construction photos.
REAL CONSTRUCTION PHOTOS · LIBERTY CANYON
A large concrete girder being installed over the 101 Freeway at night.
PHOTO COULD NOT LOADThe story still works. Tap the next step to continue.
STEP 1 OF 5 · APRIL 2024

FIRST, BUILD THE SPAN.

Crews lifted enormous concrete girders across the freeway at night. This created the structure that everything else would sit on.

Photo courtesy of Caltrans
WHO CAN USE THE CROSSING?Not just mountain lions. Many different animals can use safer, connected habitat.
Mule Deer photo
MULE DEER
Mountain Lion photo
MOUNTAIN LION
Bobcat photo
BOBCAT
Raccoon photo
RACCOON
Coyote photo
COYOTE
Black Bear photo
BLACK BEAR
Skunk photo
SKUNK
Opossum photo
OPOSSUM
Squirrel photo
SQUIRREL
Rattlesnake photo
RATTLESNAKE
Mountain lion and cub in connected natural habitat near a wildlife crossing.
FINAL · SMALL ACTIONS, BIG IMPACT

Small projects can make a BIG difference.

When communities work together, there can be hope for a better future.

Sources and science notes

The interactive story uses kid-friendly language, but the key facts are grounded in National Park Service, Caltrans, and the current Wallis Annenberg Wildlife Crossing project site. Project schedules can change; the opening date below reflects the project announcement available in September 2026.

National Park Service · 25+ years of wildlife research

Documents the 101 as a major movement barrier and research showing genetic effects in mountain lions, bobcats, coyotes, western fence lizards, and wrentits.

National Park Service · Mountain lions face loss of genetic diversity

Explains how freeway isolation reduces genetic diversity and why restoring habitat connectivity is critical for the local mountain lion population.

National Park Service · Puma Profile: P-22

NPS says P-22 was born west of Griffith Park and therefore likely crossed both the 405 and 101. He then lived for more than a decade in the unusually small, isolated Griffith Park home range.

Wallis Annenberg Wildlife Crossing · P-22 and the crossing

The project describes P-22 as the face of the Save LA Cougars campaign and says his story helped inspire the crossing. The crossing is about 30 miles west of Griffith Park and was not intended to provide P-22 himself a route out.

Caltrans · Wallis Annenberg Wildlife Crossing

Official location, species rationale, and current bridge dimensions: about 210 feet long over US-101 and about 174 feet wide.

Construction photo progression

Slide 6 uses real construction photographs from Caltrans/CDFW and LAist for the build stages, then a Pew Charitable Trusts illustration to show the finished wildlife-crossing idea.

Wallis Annenberg Wildlife Crossing · official project site

Current project announcement: opening for the animal world on December 2, 2026.