Roman Warehousing

By Chris Mundigler

In the last four issues of Labyrinth, we saw how procurement, trade and use of spices – and especially pepper – in the ancient world was nothing to sneeze at.  But how were commodities – such as spices, oils, wines and grain – stored prior to distribution in the vast empires that they helped build, both financially and gastronomically?

All of these commodities were of paramount importance to the developing empires of ancient times, and we’ve seen how they grew in importance on a global scale throughout the ancient, Medieval and modern worlds.  We’ve seen how some of the greatest civilizations in the ancient world grew, used and traded these necessities of life, and we’ve also looked at how vessels – whether ships or amphorae – were used to transport them around the known world.  But how do you effectively store such vast quantities of foodstuffs to feed an empire?

Simple underground storage bins and fields of sunken dolia (large storage containers for grain, oil and wine) may have been sufficient to suit the needs of smaller settlements or local grocery store needs of the citizenry.  But how do you accommodate the needs of burgeoning populations, or a head-count of more than a million people in Rome at the height of its power?  As with most things, the Romans simply took an older idea and made it better.  They took the simple storage layouts from the ancient Near East, Egypt and Greece, and developed them to such a high state that, other than robotic forklifts and computerized inventory control systems, we still use warehouses today in much the same way as they did.

Most Roman settlements – whether forts, towns or major cities around the Empire – had some form of horrea, or storage facility, mainly for grain.  In fact, the Latin word for grain, horreum, is at the root of this building we would call a warehouse.  Despite this, these warehouses were not just used for grain – at first, they stored mainly the grains, wines and oils that kept the Romans sustained, but eventually they were used to store almost any commercial product that was bought, sold or traded.  Because of this link to the economy of the settlements, the horrea were usually built near a waterway or port to facilitate the import and export of goods. 

Beyond this, the warehouses accommodated more than just essential products for the masses – they also held more exotic and luxury products, such as spices.  There were even specialized storehouses that catered to only one product which the Romans became almost addicted to: pepper.  For this reason, in the 1st century AD, we see the establishment of horrea piperataria – pepper warehouses – in Rome, and elsewhere. 

From literature, government records and inscriptions, we know that there were both private and public horrea, and that the administrators of the public facilities were called horrearii.  These officials were not only in charge of the public warehouses, but in the case of the public granaries, they also oversaw the distribution of the grain supply to the general public in times of famine or need – sometimes free to the poor, sometimes at a nominal price.

While horrea are mentioned throughout Roman literature – in Virgil, Horace, Cicero, Pliny, Seneca, Columella and Vitruvius, to name just a few – we also have extensive physical evidence for their construction and use as well.  In Rome itself, there’s both primary and secondary evidence of the extent and importance of these horrea to the general populace and the economy of the state.  We have a man-made gauge for the increase in trade and commerce, stored in ancient Roman warehouses, in the form of a 35 meter high mound of broken pottery that measured almost a kilometer in circumference.  The mound, called Monte Testaccio for the ceramic fragments of which it’s made, is composed mostly of amphora shards from some 50 million transport containers which carried mostly olive oil into Rome from Spain and Africa.  These amphorae were brought into Rome mostly from its port facility at Ostia Antica, some 26 kilometers to the southwest on the Tyrrhenian Sea coast, and stored in Monte Testaccio’s adjacent horrea, of which there were more than 300 in Rome in the 4th century AD.  From there, the used and discarded amphorae were heaped onto an ancient landfill between the 1st and 3rd centuries AD, which eventually became the modern tourist attraction and scholarly time-capsule known as Monte Testaccio.

Ostia Antica contains wonderful examples of these ancient horrea (figure 1), first built there around the 2nd century AD for the storage and transport of African and eastern grain shipments into Rome to supply her growing population. From the Ostia horrea, the goods were then transported along the Tiber River into Rome via barges, towed along by oxen walking the shoreline.

Figure 1.  Entrance to the 2nd century AD horrea of Epagathiana and Epaphroditiana. Photo by Chris Mundigler

These warehouses were generally of two basic types:  one, for the short-term storage of goods in transport (which were usually contained in sacks or amphorae); and two, for the long-term storage of goods to be kept on-hand for local distribution in large underground containers and dolia, some as wide as a man is tall, and usually buried to their rims in the ground.  The warehouses themselves were usually quite simple:  a row of deep, narrow, dark, cool and dry rooms.  This design is by no means unique to Rome, though.  Even before the Romans, similar designs with only slight variations are also found in Asia Minor, North Africa, and even Minoan Crete.

Generally speaking, these horrea had floors that were slightly raised off the ground so that air could freely circulate through the building to keep the products cool and dry while in storage.  Walls were often buttressed from the outside to prevent them from buckling under the pressure of the stored material inside.  The interiors of the walls were often coated with olive oil lees (amurca) and plaster, both for waterproofing and as a form of insecticide – always useful when dealing with the storage of foodstuffs over long periods of time.  These one-storey warehouses often had a window at the top of one of the walls for light and a ventilation shaft for air circulation, again, to help in preserving the goods inside.  In size, the horrea varied widely from about 20 metres long by 5 meters wide, to 35 meters long by 20 meters wide, but all were used for the same purpose:  to store and preserve the vital food supplies required by a growing Empire in an uncertain world of invasion, corruption, natural disaster and the wrath of the gods.