The free rations are sitting on the eastern edge of Berlin’s Tempelhofer Feld, a sprawling former airfield whose decommissioned runways have become a public park. The Feld, as it’s known locally, was once the main stage for the Berlin Airlift, the 15-month operation to get food and supplies to blockaded West Berliners during the cold war. The potatoes delivered this morning, however, are part of an entirely different rescue mission, one undertaken on behalf of the spuds themselves.