It's a six-month expedition in almost constant darkness, in the coldest place on Earth, with no chance of rescue if things go wrong. British explorer Sir Ranulph Fiennes calls it one of the last remaining polar challenges: crossing Antarctica during winter.
Fiennes, 68, and his five-member team left Cape Town, South Africa, on Monday aboard a polar vessel for what they have dubbed "the Coldest Journey."
After reaching the southernmost continent, the expedition will begin its journey via the South Pole on March 21, traversing nearly 2,485 miles in a place where temperatures often dip as low as minus 94 Fahrenheit.
The trip is particularly hazardous because if disaster strikes, no aircraft can travel inland in the winter due to the darkness and risk that fuel will freeze.
"Some people will say it is irresponsible to go unless you know everything, in which case the Americans would never have gotten to the moon. If humans are going for something new, then unfortunately there are bound to be some gray areas," Fiennes said.
Satellite and other communications technology will allow the team to communicate with the outside world.