Sentence:  Buried within the Mediterranean littoral are some seventy to ninety million tons of slag from <WSD>ancient</WSD> smelting, about a third of it concentrated in Iberia. This ceaseless industrial fueling caused the deforestation of an estimated fifty to seventy million acres of woodlands. 
Meaning of the word marked with <WSD> tags:  Existent or occurring in time long past, usually in remote ages; belonging to or associated with antiquity; old, as opposed to modern.