The first layers of soil were recently placed in Agoura Hills on what will be the world's largest wildlife crossing.

The Wallis Annenberg Wildlife Crossing over the 101 ... to be built in such a densely populated urban area," Beth Pratt, California's executive director for the National Wildlife Federation ...

The soil, to cover nearly an acre of the Wallis Annenberg Wildlife ... the crossing is provided by the Annenberg Foundation, other private donations, and the California Wildlife Conservation ...