An amateur diver off the coast of Israel has discovered a sword that is likely to have belonged to a Crusader knight who sailed to the Holy Land almost a millennium ago.

Shlomi Katzin came across the 900-year-old weapon on the floor of the Mediterranean sea while scuba diving Saturday off the Carmel coast in northern Israel, the Israel Antiquities Authority said in a statement.

Experts said that the ancient sword was probably uncovered after sand was shifted by waves. Other artifacts found in the weapon’s vicinity included metal anchors, stone anchors and fragments of pottery.

Israeli law requires any artifacts found to be returned to the nation. After his discovery, Katzin said he retrieved the sword from the seabed out of concern that the find would be stolen or reburied. He turned it over to authorities and was awarded a certificate of appreciation for “good citizenship.”

The sword, measuring about four feet long, was encrusted in marine life but in otherwise “perfect condition,” according to Nir Distelfeld, an official with the IAA.

Distelfeld, in a statement, described it as a “beautiful and rare find” that probably belonged to a Crusader knight. “It is exciting to encounter such a personal object, taking you 900 years back in time to a different era, with knights, armor and swords.”

Israel’s northern coast has many coves where ancient ships found shelter from storms, said Kobi Sharvit, a marine archaeologist with the IAA, adding that old port cities and other human settlements were built around larger coves.

“These conditions have attracted merchant ships down the ages, leaving behind rich archaeological finds,” he said in a statement.

Experts say the discovery of ancient artifacts by swimmers and recreational divers has become increasingly common in recent years amid the growing popularity of water sports in the region. The site where the sword was found has been monitored by authorities since it was first discovered in June.

Other finds in the area show the anchorage was used as early as the late Bronze Age, or about four millennia ago. The recent discovery of the sword suggests that the natural cove was also used during the Crusades, Sharvit said.

During the Crusades, which ran from the late 11th century through the late 13th century, fortified settlements were built in the Holy Land by knights from Europe trying to establish a Christian kingdom with Jerusalem as its capital.

Muslim forces did not travel by sea, which Sharvit said indicated the sword was a Crusader weapon, according to Haaretz.

Experts say the warm temperatures of the Mediterranean probably helped preserve the iron sword. Marine life stuck onto the weapon “like glue” as the iron oxidized, Sharvit told the New York Times on Monday.

Authorities intend to put the sword on display after it has been cleaned and researched. Eli Escosido, general director of IAA, praised Katzin in a statement for handing over the artifact to authorities. “Every ancient artifact that is found helps us piece together the historical puzzle of the Land of Israel.”

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