Alcohol enthusiasts typically turn to estate sales, auction houses or specialized bars to find rare, decades-old spirits.

Treasure hunters in Scandinavia, however, have recovered dozens of cases of cognac and liqueur from a far more unusual location: 250 feet under the surface of the Baltic Sea.

The liquor was recovered last month from the wreckage of the S.S. Kyros, a Swedish steamship, in international waters between Sweden and Finland, where the ship sank in 1917 after being attacked by a German submarine during World War I. The Germans had determined the ship, which was headed to Russia, was carrying contraband, according to Ocean X Team, a Swedish search and salvage company that participated in the recovery.

“The importance of this event cannot be overemphasized — it’s not only a find of rare cognac and liqueur but also a part of history of the former imperial Russia,” Ocean X Team said in a news release describing the recovery.