Dia Archaeological Site is an archaeological site located in the town of Dia in the Mopti Region, Mali, on the western edge of the inland Niger River Delta. The settlement complex at Dia consists of 3 separate large archaeological mounds, namely, Dia-Shoma, Dia, and Dia-Mara. The site of Dia-Shoma is the largest and oldest among them, dating back to the 9th century BC, while settlement at Dia-Mara dates back to more recent historical periods in the 6th century AD. Proximity to water resources made Dia favorable for trade between the south and north of the Sahara, until it became one of the main trade sites in the region.