Tanais
| Τάναϊς Танаис | |
| The archaeological park of Tanais. May 2017 | |
| Location | Nedvigovka, Rostov Oblast, Russia | 
|---|---|
| Region | Maeotian marshes | 
| Coordinates | 47°16′8″N 39°20′6″E / 47.26889°N 39.33500°E | 
| Type | Settlement | 
| History | |
| Builder | Settlers from Miletus | 
| Founded | Late 3rd century BC | 
| Abandoned | Second half of the 5th century AD | 
| Periods | Hellenistic to Late Antiquity | 
| Cultures | Greek, Sarmatian | 
| Site notes | |
| Condition | Ruined | 
| Ownership | Public | 
| Public access | Yes | 
| Website | museum-tanais | 
Tanais (Greek: Τάναϊς Tánaïs; Russian: Танаис) was an ancient Greek city in the Don river delta, called the Maeotian marshes in classical antiquity. It was a bishopric as Tana and remains a Latin Catholic titular see as Tanais.