Adamclisi

In ancient times, a Roman castrum named Civitas Tropaensium was settled here and in 109 AD a monument named Tropaeum Traiani was built to commemorate the Roman Empire's victories over the Dacians.

Colonized with Roman veterans of the Dacian Wars, the city was the largest Roman city of Scythia Minor and became a municipium in the year 170. Destroyed by the Goths, it was rebuilt during the rule of Constantine the Great with better defensive walls, which defended the city successfully until the Avars sacked it in 587. After that moment, it ceased to be among the important cities of Dobrogea and was no longer mentioned for seven hundred years.

Wikipedia