EFELos Angeles

Construction on what is being called the world's largest wildlife crossing, a bridge that will give mountain lions, coyotes, deer, snakes and other animals a safe route over an eight-lane highway, kicked off on Friday in Southern California to coincide with Earth Day.

After more than a decade of public and private efforts, work has finally begun on a bridge - the Wallis Annenberg Wildlife Crossing - that will connect the coastal Santa Monica Mountains to the area north and south of the Santa Susana Mountains.