Through "Iceberg Alley"

From an old slide, taken January 1966. Relatively shallow water off the coast near the Wilkes/Casey base results in many large icebergs being grounded, sometimes for years, so the area acquired the label of "Iceberg Alley". Most are tabular bergs, as seen here. In turn, the grounded icebergs tend to keep the sea ice from drifting away, sometimes causing shipping access problems.

In the PiP, the ship working slowly fore and aft, pushing its way through the pack ice.