The American Base at McMurdo is sometimes on the itinerary of cruise ships, it is far and away the largest Antarctic base with a summer population (when the tourist ships can get in) of around 1000 falling to 250 in the winter.
The next largest base has a summer compliment of 250 with several more in the 100's. 80%+ of bases have a summer compliment of less than 100 people, the winter crew is usually between about a half and a quarter of the summer compliment.
Antarctic Bases - Seasonal Populations
Photo; Â© Mike Usher - Pictures from an icebreaker cruise to Eastern Antarctica.