The city's economy included fishing and preparing salt fish, as shown by the industrial complex located in today's San Nicolas street of the
Villa Vieja (Old Town) of Algeciras. It dates from the first century until probably late fifth or early sixth centuries. Many millstones were found in five fish-processing factories, and many traces of fish, but very few bones. This suggests that the factories were involved in grinding down the bones to manufacture flours of fish. The salting factory stretched across much of the
Villa Vieja, from San Nicolas street probably to the south of the
Hotel Reina Cristina. The remains of the salting vats have been located at the foot of the medieval towers of the
Villa Vieja, confirming the extent of the complex. In the first century BC Iulia Traducta had a
mint which has left abundant
coins (dupondios, asses, semisses and quadrants), clearly showing the importance of the fishing and industry of the town, issued between the years 12 and 10 BC. Creation of this mint was part of the propaganda drive by
Octavius to show the divine character of the emperor. The coins minted in the city showed the image of the emperor, his sons Gaius and Lucius and the priestly attributes of
princeps of Rome. It also showed symbols related to the economy of the city such as tuna. It is possible that part of the population also undertook the manufacture of wine, since many amphorae intended for this purpose have been found. The production of amphora in Traducta Iulia has been considered minor due to the existence of a major complex for manufacturing amphorae in the neighboring city of Portus Albus, but nevertheless there were potteries in Traducta judging by some findings around the beach of Chorruelo next to the factories and nearby lands south of the factories. These kilns for making the amphorae have been dated to the first century AD. They may have replaced kilns located in Portus Albus that had been abandoned at that time. From this it would seem that there was an increase in the economic importance of the city at the expense of nearby Carteia, whose amphorae production depended on manufactures of Portus Albus. The extent of Iulia Traducta is unknown, although it is supposed to have occupied the
Villa Vieja of Algeciras. The area where material has been found extends to the lower part of the
Villa Nueva on land beside the
Río de la Miel. The river's estuary, now silted up by alluvial deposits, served as a port for landing fish. ==Later history==