Antarctica is the landmass currently located over the South Pole, but it hasn’t always been there. Over hundreds of millions of years, different portions of the ancient supercontinent Gondwana drifted across the polar position. During the Late Ordovician period, around 445 million years ago, what is now western Africa sat near the South Pole. The story of which land occupied the bottom of the world is really the story of continents in constant motion.
Gondwana: The Southern Supercontinent
The short answer to this question, especially as it appears in geology and earth science courses, is Gondwana (sometimes called Gondwanaland). This massive southern landmass was clustered near the South Pole for hundreds of millions of years before it began breaking apart roughly 200 million years ago. Gondwana contained the modern continents of Antarctica, South America, Africa, India, and Australia, all fused together into a single enormous block of continental crust.
Gondwana itself was the southern half of an even larger supercontinent called Pangaea, which included nearly all of Earth’s landmasses. When Pangaea split, the northern portion (Laurasia, containing North America and Eurasia) separated from the southern portion (Gondwana). But Gondwana had existed as a coherent landmass long before Pangaea formed, stretching back more than 500 million years.
The South Pole Wasn’t Always Under Antarctica
Because continental plates move slowly across Earth’s surface, the geographic South Pole has been covered by different parts of Gondwana at different times. During the Late Ordovician, about 445 million years ago, the south pole sat close to what is now western Africa. A massive glaciation developed across Gondwana during this period, leaving glacial deposits that geologists have found in the Saharan region of modern Algeria and surrounding areas. The idea of ice sheets covering the Sahara sounds bizarre, but that part of Africa was polar terrain at the time.
As Gondwana drifted, the polar position shifted to other regions of the supercontinent. By the late Paleozoic era (roughly 350 to 250 million years ago), parts of what would become Antarctica, Australia, and India rotated closer to the pole. Glacial deposits and distinctive fossils from this period are found across all the former Gondwanan continents, evidence that they shared a connected, partially frozen landscape.
How Scientists Know Where Continents Were
Reconstructing the positions of ancient continents relies heavily on paleomagnetism. When rocks form, iron-bearing minerals inside them align with Earth’s magnetic field like tiny compass needles, then lock in place as the rock solidifies. By measuring the direction and angle of these magnetic signatures in rocks of known ages, scientists can calculate what latitude a continent occupied when those rocks formed. Combining paleomagnetic data with geological and tectonic evidence produces detailed maps of ancient continental positions going back over a billion years.
Fossil evidence provides powerful confirmation. In the 1960s, leaf impressions of Glossopteris, a seed fern that thrived in cool, moist climates, were discovered in the Ellsworth Mountains of West Antarctica. These were the first Glossopteris fossils and the oldest identifiable plant fossils found in West Antarctica. The same plant appears in rocks from South America, Africa, India, and Australia, all in geological layers of similar age. This distribution only makes sense if those continents were once joined together near the pole, exactly where paleomagnetic data places Gondwana. Coal deposits found alongside these fossils indicate periods when the polar regions supported lush vegetation between glacial episodes.
Antarctica Settles Over the Pole
As Gondwana broke apart, Antarctica gradually migrated to its current polar position. One of the critical events in this process was the opening of the Drake Passage, the waterway between South America and the Antarctic Peninsula. New research dates this initial separation to between 62 and 59 million years ago, caused by a clockwise rotation of the Antarctic Peninsula away from South America.
This opening had enormous consequences. Once the Drake Passage formed, a shallow circumpolar current began flowing around Antarctica, cutting it off from warm subtropical ocean waters that had previously reached its shores. Global ocean circulation patterns shifted, and temperatures dropped. Still, it took millions of years more for the continent to fully freeze. Permanent glaciation of Antarctica began around 34 million years ago, initially confined to East Antarctica. Ice didn’t advance to the West Antarctic coast until at least seven million years later, roughly 27 million years ago.
Today, Antarctica sits almost perfectly centered on the South Pole, buried under ice sheets up to 4.8 kilometers thick. It is the only major landmass currently positioned over either pole, a situation that is geologically temporary. The same tectonic forces that pushed it there will eventually carry it elsewhere, though on a timescale of tens of millions of years.
Why This Question Matters
Understanding which landmass sat over the South Pole at various points in history isn’t just trivia. It explains patterns of ancient climate, the distribution of fossils across continents that are now separated by oceans, and the formation of mineral and energy resources. Glacial deposits found in the middle of the Sahara, coal seams in Antarctica, and identical plant fossils on five continents all trace back to the slow drift of Gondwana across the South Pole over hundreds of millions of years. The current arrangement of continents, with Antarctica isolated and frozen at the bottom of the world, is just one frame in a very long film.