Pan Am went over the south pole.

Several people have flown over the south pole.

https://www.aopa.org/news-and-media/all-news/2015/january/22/around-the-world-over-the-poles

http://transglobe-expedition.org/expedition/

It's been circumnavigated by many sailors, all with times consistent with a 14,000 ish mile continent and not a 60,000 mile ice wall.

http://www.ybw.com/news-from-yachting-boating-world/lisa-blair-begins-world-record-attempt-circumnavigate-antarctica-47089

http://yachtpals.com/boating/antarctica-boats

And it's been crossed on foot from one side to the other.

https://www.wired.com/2016/02/people-cross-antarctica-all-the-time-its-still-crazy-hard/

Pretty clear Antarctica is a circumnavigable continent.