Archaeologists have found an ancient cargo ship full of hundreds of jars at the bottom of the sea off the coast of Civitavecchia, a port town about 70 kilometres north-west of Rome.

The ship, known as an oneraria, was said to date back to the 1st or 2nd century AD and experts estimates that it measured over 20 metres long.

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Archaeologists from Italy’s cultural heritage protection police squad, or Carabinieri Comando Carabinieri per la Tutela del Patrimonio Culturale (TPC), made the discovery along with scuba divers from the national superintendency for underwater cultural heritage, an institution that protects and regulates underwater heritage sites.

Most of the jars, or amphorae, were reportedly intact, and heritage experts were still working out exactly what they were used for.

“This exceptional discovery represents an important example of the sinking of a Roman ship which faced the perils of the sea in an attempt to reach the coast and bears witness to the ancient maritime trade routes,” the cultural heritage protection police unit said in a statement.

The wreck was still anchored to the sandy seabed, lying at a depth of 160 metres.

As can be seen in the police video below, the team used a remotely operated robot to make the discovery and map the underwater archaeological site.

Watch how the experts made the discovery here: