Archaeological site Monte Testaccio in Rome

You're standing at Monte Testaccio, a hill in Rome with a remarkable secret. Take a good look at its slopes. This hill wasn't made by nature, but by people. It's built almost entirely from fragments of broken Roman jars, called amphorae. The remains of an estimated fifty-three million of them are buried here. The mound stands thirty-five metres high, with a circumference of nearly a kilometre, and in ancient times it was probably quite a bit taller.