Two amateur divers discovered Israel’s biggest haul of underwater Roman-era artefacts in three decades, it has been revealed , as the priceless objects were shown for the first time.

The treasures were found last month by Ran Feinstein and Ofer Raanan when they were exploring a sunken ship close to the ancient port of Caesarea. “It took us a couple of seconds to understand what was going on,” Raanan said.

They initially left the first sculpture on the seabed, but then when they discovered a second, they realised it was something special and brought it to the surface. They later searched the area and uncovered more.

“It was amazing. I dive here every other weekend and I’ve never found anything like that, ever,” he continued.

Figurines of the moon goddess Luna and Dionysus, the god of wine. Photograph: ZUMA Wire/Rex/Shutterstock

The Israel Antiquities Authority (IAA) sent down its own divers to investigate further and recover the treasure, which includes bronze statues, lamps, jars, animal-shaped objects, anchors and thousands of coins featuring images of the Roman emperors Constantine and Licinius.

Some of the objects date back to the fourth century AD, while others are from the first and second centuries, said Jacob Sharvit, the director of marine archaeology at the IAA.

Sharvit said it was likely that the ship’s sailors had thrown down their anchors in a storm, but after their attempts failed, the ship drifted and all its cargo plunged into the Caesarea port waters, where it remained for 1,700 years.

The port was commissioned by Herod the Great in the first century BC and became an important economic artery in the Mediterranean until it sank for unknown reasons soon after its completion.