Antarctica was a continent on planet Earth, comprising much of the planet's southern polar region. It is considered one of the most inhospitable regions on Earth, given its constant sub-freezing temperatures and regular storms.
The Da Vinci Research Base was a top-secret laboratory established in Antarctica, with the purpose of monitoring and adjusting the Earth's ozone layer. It was destroyed in 1984 by Gary Seven and Khan Noonien Singh. (TOS novel: The Rise and Fall of Khan Noonien Singh, Volume 1)
In the 1990s, the Byrd Research Complex was built near the Ross Ice Shelf. It was abandoned later that same decade, but revisited in 2045 during the investigation of two extraterrestrial visitors. (TOS novel: Strangers from the Sky)