Monte Testaccio is an artificial mound in Rome composed almost entirely of fragments of broken amphorae dating from the time of the Roman Empire. It is one of the largest spoil heaps found anywhere in the ancient world, covering an area of 20k m2 at its base and with a volume of 580k cubic m, containing the remains of an estimated 53m amphorae. It has a circumference of nearly 1km and stands 35m high, though it was probably considerably higher in ancient times.