The northeastern reaches of the Ancient Greek Empire extended to the Don River delta, which was then at the mouth of the Sea of Azov. The sea has receded, but the evidence of Greek trading cities remain at archaeological sites such as Tanais, about 30km west of Rostov. The 26-hectare site features the remaining walls of the fortified citadel, as well as a museum packed with artefacts and a few reconstructions of ancient structures.
The Tanais archaeological site is near the village of Nedvigovka, about halfway between Rostov and Taganrog. To get there, take an elektrichka from the local train station in Rostov. You can also catch bus 158, or marshrutka 458 from the central market (R65, one hour) at 6am, 8am, 9.30am, noon or 1.30pm, returning at 11.10am, 1.50pm or 6pm. There's no restaurant on site, so you may wish to pack a picnic.