Oescus

Oescus, Palatiolon or Palatiolum was an important ancient city on the Danube river in Roman Moesia. It later became known as Ulpia Oescus. It lay northwest of the modern Bulgarian city of Pleven, near the village of Gigen.

For a short time it was linked by the longest and most famous stone bridge across the Danube, Constantine's Bridge, with the ancient city of Sucidava.The city seems to have at one point reached a area of 280,000 m2 and a population of 100,000.Archaeological excavations have brought to light parts of the ancient city and are continuing.