(CNN) -- It's as tall as some of L.A.'s highest skyscrapers, but the only residents here are rats and cockroaches.
Welcome to the Puente Hills Landfill, the largest rubbish dump in America. Over 150 meters of garbage has risen from the ground since the area became a designated dumping site in 1957.
Now, six days a week, an army of 1,500 trucks delivers a heaving 12,000 tons of municipal solid waste from the homes and offices of L.A. County's millions of inhabitants.
"This used to be a dairy farm; a valley filled with cows producing milk. And now it's a geological feature made out of trash," said Edward Humes, author of "Garbology: Our Dirty Love Affair with Trash" -- a book that charts the history of garbage in America.
Humes says most of the waste arrives straight from the bins of local residents.
"If you're like most of us -- most Americans -- you're making seven pounds of trash a day. Across a lifetime that adds up to 102 tons of trash per person," he said.
