Shards of amphorae, or vases, discovered at the ancient Roman landfill known as Monte Testaccio, in Rome.
The amphorae found in this ancient dump site have been useful to archaeologists and historians studying the consumption, trade and transport of olive oil in the Roman Empire.
An aerial view of Monte Testaccio
Archaeologist Dr. Richard Meadow has worked on excavating the ancient city of Harappa in present-day Pakistan.
Ancient walls show progressive deposits of debris; according to Meadow, ancient peoples would often dump their trash in the streets, causing street levels to rise and forcing people to keep building higher and higher.