The castra is located on the coast of Maciuca hill, 2.5 km from the town of Oltina, on the Danube.
The camp covers an area of 2 hectares. Procopius is the one who mentions this settlement, the Altinum (or Altenum) colonies. The historians Irimia and Emilia Popescu did some research, after which they discovered: a military diploma in bronze dated August 14, 100, an amphora with the inscription “HRISTON MARIA GHENA” (Maria is born on Christ), a Byzantine ceramic burner from the IV-VI centuries, inscribed bricks, coins from Diocletian and Constantine the Great, and ceramic vessels.
The name Altenum was preferred in order to differentiate the new colony from the ancient city of Altinum, which is the modern city of Altino in northern Italy. At Altenum (Altinum), there was also a civil settlement, as well as a station of the Roman river military fleet, between the I – IV centuries AD.. I – IV AD. In the past, the settlement had a port at the Danube, but in present times, the port is disbanded due to the clogging of the Danube arm.