I saw a tweet today of a woman with cancer running 7 marathons in 7 days on 7 continents. 7 continents? Did she set up a personal marathon along the Antarctic coast? No.
There is actually an Antarctic marathon and it's held annually at Union Glacier, a privately run tourist camp at almost 80 degrees south. It's serviced by Il-76s. You have to watch this video.
What's more, there is an outfit that will let you do 7 marathons in 7 days on 7 continents for 36,000 euros (which is much less than I thought it would cost). The itinerary: