Road station
Tierua
Orşova
Tierua is Dierna, today Orșova on the Danube at the Iron Gates in Romania, a Dacian settlement that became Roman under Trajan. The jurist Ulpian says Trajan made it a colony with Italian rights; it was a station of the Illyrian customs, made its own roof tiles, and after Rome gave up Dacia it still kept a legionary garrison. From here the road ran to Tibiscum and Sarmizegetusa. The old name lives on in the river Cerna, and the map's Tierua seems to be a slip for Tierna.