Ancient Roman coins found buried under Japanese castle

Ancient Roman coins found buried in the ruins of a Japanese castle have left archaeologists baffled.

A Japanese archaeologist identified 4 Roman coins that dated back to around 400 AD.

The coins were discovered beneath Katsuren Castle on Okinawa Island along with some Ottoman coins.

But Experts are stumped as to how the Roman coins got to Uruma -- they suspect trade but cannot trace an exact route.

One archaeologist said he thought at first they were one-cent coins dropped by U.S. soldiers.

X-ray analysis confirmed one of the coins resembles Roman Emperor Constantine The Great.

While another coin depicts a soldier wielding a spear.

The coins are on display at a Uruma City Historical Museum.

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