Salinae Gaditanae
About
Salting factories lined the channel banks at Eritheia, the island district of ancient Gades, feeding a fishing industry already flourishing before the 1st century BCE. Almadraba tuna caught in the strait went straight from these salt pans into the garum vats that made the city's fish sauce famous across the empire. By 117 CE Gades had built two centuries of Roman-era wealth on the salt harvested from its own tidal flats.
What happened here
Shallow pans are cut into the flats behind a beach or a lagoon and filled at high tide through a gate. The water is walked through a sequence of pans, each shallower and saltier than the last, and the sun does the rest over the summer. In late season the crust is raked into ridges, left to drain, then carried off in baskets. The work is hot, glaring and hard on the feet, and it is done by contracted labour on a short season. Salt preserves fish and meat, cures hides and pays part of the state's revenue, so the pans are regulated and often leased from the state. A salina needs sun, wind and a tide, and it shuts down entirely when it rains.
Sources
Roman Maps shows the empire frozen at 11 August 117 CE, the day Trajan died — its moment of greatest territorial extent. Explore the full map →