The bone on the right is the newly discovered fossil; the other is a sample sloth bone.
The bone on the right is the newly discovered fossil; the other is a sample sloth bone. LA Metro

Underneath Los Angeles, there’s a wealth of fossils from ancient creatures. The conditions in the area were perfect to trap and preserve giant mammals that lived more than ten thousand years ago, and as the Los Angeles Metro authority digs tunnels to accommodate the city’s expanding subway system, workers keep finding more fossil treasures.

Most recently, they uncovered a fossilized hip joint of what was like a Harlan’s ground sloth, one of the species of giant sloth that roamed North and South America in ages past. Compared to the sloths of the today, ancient ground sloths were giant: a Harlan’s ground sloth could have grown to 10 feet in length and weighed 1,500 pounds.

The bones were found 16 feet below Crenshaw Boulevard, the L.A. Metro’s blog, The Source, reports, and will be held by National History Museum of Los Angeles County or another museum.