Ports and harbors of Antarctica

right|thumb|290px|The Nathaniel B. Palmer (icebreaker)|RV Nathaniel B. Palmer research vessel using the iceport at [[Bay of Whales, Antarctica.]] An iceport is a more-or-less permanent indentation in the front of an ice shelf, that can serve as a natural ice harbour. Though useful, they are not always reliable, as calving of surrounding ice shelves can render an iceport temporarily unstable and unusable.