who led the explorers?
Robert Falcon Scott and Ernest Shackleton
Farthest South
After the first overwintering on continental Antarctica in 1898–99 (Adrien de Gerlache), the prospect of reaching the South Pole appeared realistic, and the race for the pole began. The British were pre-eminent in this endeavour, which was characterised by the rivalry between Robert Falcon Scott and Ernest Shackleton during the Heroic Age of Antarctic Exploration.
what is farthest south? It is the most  southerly latitude reached by explorers before the conquest of the South Pole in 1911.
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Farthest South [SEP] Introduction
This caused a shift of emphasis in the first half of the 19th century, away from trade and towards sealing and whaling, and then exploration and discovery. After the first overwintering on continental Antarctica in 1898–99 (Adrien de Gerlache), the prospect of reaching the South Pole appeared realistic, and the race for the pole began. The British were pre-eminent in this endeavour, which was characterised by the rivalry between Robert Falcon Scott and Ernest Shackleton during the Heroic Age of Antarctic Exploration. Shackleton's efforts fell short; Scott reached the pole in January 1912 only to find that he had been beaten by the Norwegian Amundsen.