Amphorae were too cheap and plentiful to return to their origin-point and so, when empty, they were broken up at their destination. In Rome this happened in an area named Testaccio, close to Tiber, in such a way that the fragments, later wetted with Calcium hydroxide (Calce viva), remained to create a hill now named Monte Testaccio 45 meters tall and more than 1 km circumference.
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GARUMThe most detailed description of garum is from the Geoponica (XX.46). The preparation involves adding a quantity of salt (two sextarii to one modius, 1:8, this is the only recipe to provide a ratio) to the entrails of small fish, such as mullets, sprats, or anchovies. The mixture then was allowed to ferment or macerate in the sun for several months, the liquamen drawn off and strained and used as a condiment or seasoning, the feculent remainder made into allec. (Frustratingly, the composition of garum begins with a description of how liquamen is made: garum is said to strain into the basket, but then the percolated liquid is also called liquamen .) A quicker means of preparation simply was to boil a fish in strong brine, add some origanum (oregano) and possibly some sapa , and strain until clear. (Galen says that oregano moderates the taste of an oily, watery fish such as the gray mullet, III.24.) The best garum , however, was made from the viscera of tuna, together with the blood, juices, and gills, salted and allowed to ferment for two months. This concoction was called haimation ("bloody"). Wine, herbs, and spices also could be added.