Archaeologists dated a Corinthian helmet to the sixth century BC, a time when the Greek city-states clashed with the mighty Persian Empire.
According to the Israeli Antiquities Authority (IAA), the Corinthian helmet was made in the Corinthian style, named after the Greek city of Corinth.
Although it is cracked and rusted after spending about 2,600 years in the water, you can still make out an intricate, peacock-like pattern above its eyes.
Archaeologists claim it is the only complete helmet of its kind ever found along Israel's coast.
The IAA, which shared the discovery on Facebook, posted: "Have we shared with you just how excited we get when we find artefacts deep in the sea?"
"Here's a discovery we're excited about: A bronze helmet, in an excellent state of preservation, was discovered in 2007 in the Haifa Harbour."
The helmet uncovered by a Dutch dredging ship in the port city in northern Israel.
The ship's owner, Mr Hugo van de Graaf, handed the discovery over to the IAA.
It is now on display at the National Marine Museum of Haifa.
Kobi Sharvit, director of the Marine Unit of the Israel Antiquities Authority, said:
"The helmet probably belonged to a Greek warrior stationed on one of the Greek fleet's warships that participated in the naval conflict against the Persians who ruled the country at the time."
The IAA added: "This helmet is the only complete example ever discovered along the coast of Israel. Do you love this as much as we do?"
The Greco-Persian wars lasted for some 50 years in the fifth century BC, lasting from 499 to 459 BC.
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