Operation Tanne Ost

Operation Tanne Ost ("Fir East") was a German operation during World War II to capture the island Suursaari (Swedish: Hogland; Russian: Гогланд, romanized: Gogland) in the Gulf of Finland before it could fall into Soviet hands. Suursaari was especially important because it worked as a lock in the Finnish Gulf guarding the minefields keeping the Soviet Baltic Fleet in Kronstadt.