Every year the team stationed in Antartica places a marker on the geographical south pole. 

Apparently the sheet of ice that sits above the south pole moves every year so the markers stay up for a few years before they are stored away.

The ceremonial South Pole is surrounded by the flags of the Antarctic Treaty Nations. You can see the dome of the Amundsen-Scott South Pole Station in the background.

Data from a GPS is used to mark the exact placement of 90 degrees south latitude. Each marker is about 12 feet long, but about two-thirds of it gets pounded into the ground. The markers are only left up for a few years before they are stored away in the South Pole Station.

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From the Upcoming ueue, submitted by boodaa.