Excavation by Oxford Archaeology in 2009 during construction of the Stanford Wharf Nature Reserve, funded and supported by the developer, DP World London Gateway, uncovered remarkable evidence for Iron Age and Roman-period salt making. The excavations shed new and important light on evolving methods of salt production, which undoubtedly reflect wider changes in economy and society in the Thames Estuary between c 400BC and c 400AD. Salt had a particular economic importance in the ancient world as a food preservative - changing scales and methods of production provide an essential background for understanding processes such as urbanisation, civilian trade and miltary supply. It also had a wide range of dietary, social and symbolic functions, from food flavouring, to an ingredient in medicines and religious rituals. In the words of the Roman naturalist Pliny the Elder, writing in the 1st century AD, 'civilised life cannot proceed without salt'.
In the middle Iron Age, from c 400BC – 100BC, the site was dominated by 'red hills', a characteristic feature of ancient salt production on the Essex coast. Following a late Iron Age hiatus, salt making resumed in the early Roman period (c AD 43-120). During this period a piled wooden structure, possibly a boathouse, was built facing onto a tidal channel. The 3rd and 4th centuries AD saw the level of salt production intensify to an almost industrial scale. Some salterns of this period were open air while the later ones were inside a variety of buildings. In some respects late Roman production methods were similar to the earlier periods but significant innovations were introduced, including lead evaporation pans and the use of wood charcoal, rather than marshland plants, as fuel. The range of activities diversified to include the on-site production of salted meat and fish sauce, and there are indications of relatively high status domestic life, notably the remains of exotic fruit and seeds.
This monograph presents the internationally important findings of three years of fieldwork and post-excavation analysis. The large scale of investigation and extensive scientific analysis of the remains has transformed our understanding of the important Iron Age and Roman salt making industry in Essex.