In response, Berlin immediately ordered its Black Sea Fleet and Danube flotilla upstream. What assembled was less a war fleet than an evacuation: more than 4,000 people aboard barges, landing craft, a hospital ship, and tugboats converted into minesweepers. But the Iron Gates gorge upstream, the convoy's only way out, was already in Soviet hands. Four attempts to break through failed, and on the night of September 6, 1944 the crews began sinking their own ships at Prahovo."The remains of the scuttled German fleet serve as a kind of war memorial, preserving the memory of an event that, as far...