Nicopolis ad Nestum or Nicopolis ad Mestum is a ruined Roman town of the province of Thracia (Thrace) near to the modern village of Garmen on the left bank of the Mesta river, in Garmen Municipality, Bulgaria. Although "ad Nestum" is the more commonly used alternative, "ad Mestum" (which is what appears, in Greek, on the coins of the city) is the correct form of the name during the Roman period.
The town was one of two fortified towns founded to mark Emperor Trajan’s victory in 105-106 AD over the Dacians. The area had been inhabited for about 14 centuries and attained its peak in late antiquity (4th-6th centuries AD). The original town occupied about 25-30 decаres. The Slavs destroyed Nicopolis in the 6th-7th centuries but it re-emerged as a medieval settlement in the late 10th century.
Excavations have cleared 280 metres of fortress walls, administrative and religious buildings and tumuli. Several archaeological finds have been made, including a votive relief of the Thracian horseman, a statuette of Hermes, an old Christian tumulus, over 95 gold and 22 other coins, glass, bronze and ceramic vessels and a ritual table. Some of these findings can be seen in the historical museum at Gotse Delchev. Close to Nicopolis ad Mestum there are remains of two early Christian basilica (4th century AD), which are believed to be part of the same site. The basilicas have mosaic floors with geometric and natural motifs.