S'Argamassa Roman Fish Farm

The islands economy also saw a huge growth in its fishing industry.[4] The fishing technique of almadraba[4] was used in the seas around the island. This used a labyrinth of nets and approximately fifty boats which channelled huge schools of fish, tuna being the main catch, into a holding area. The fish were then culled and dragged aboard the fishing boats. However these catches were so bountiful that not all the fish were killed. Some of the fish were kept alive in aquatic enclosures such as this one, along with a fish processing plant, built by the Romans at S'Argamassa.[4]

Leading to the processing plant on the coast, the Romans constructed an aqueduct[4] to carry fresh clean water from a nearby stream to the processing plant. Part of this aqueduct can still be seen today. The conduit is built from large limestone slabs[4] with a channel carved into the top surface. Unfortunately it is rather neglected these days but a 425-metre (1,394 ft) run of it can still be seen as it runs down to the coast alongside a modern hotel complex.

What the processing plant at S'Argamassa may have looked like.

When the fish surplus was brought to S'Argamassa, it was dealt with in two ways. The fish was filleted and then dried and salted. This product was called Salazón. The byproduct of the filleting process was used to produce the Roman delicacy of garum.[5] Garum is a fish sauce which was consumed in great amounts in the Roman Empire. The heads, tails, gills, innards of the fish were first boiled and then macerated in salt, and cured in the sun for one to three months. The mixture fermented and liquefied in the dry warmth, with the salt inhibiting the common agents of decay. Garum was the clear liquid that formed on the top, drawn off by means of a fine strainer inserted into the fermenting vessel. The sediment or sludge that remained was allec.[5] Concentrated decoctions of aromatic herbs might be added. Flavours would vary according to the locale, with ingredients sometimes from in-house gardens.[6]

At the end of the run of the aqueduct close to the shoreline there are the remains of rectangular structures which were once the fermenting tanks for the production of the garum. On completion of the process the sauce was packed into enormous earthenware storage jars called amphoras,[7] also produced locally, and exported to all parts of the empire. The sauce was hugely popular condiment and was the ketchup or soy sauce[7] of its day.