John Kerry became the highest-ranking US official to visit Antarctica on Friday, when he landed there for a two-day trip during which he will hear about the impact of climate change on the frozen continent.
US Secretary of State Mr Kerry left from New Zealand after being held up for about a day by bad weather.
Mr Kerry and his entourage left Christchurch airport at 6am aboard a C-17 Globemaster military cargo plane and landed in Antarctica about 11am local time on Friday.
Mr Kerry, an experienced pilot, spent much of the flight in the cockpit of the huge jet, chatting with the pilots.
After a smooth trip of about five hours, the group landed on the Pegasus Ice Runway, the strip of ice that serves McMurdo station. The large base is the hub for US operations.
Mr Kerry made no public remarks on the initial leg of the trip.
In Christchurch a day earlier, he congratulated President-elect Donald Trump for winning a "momentous election" and said he had reminded State Department staff of the "time-honoured tradition of a very peaceful and constructive transfer of power".
In Antarctica, his plans called for his entourage to transfer immediately at the airstrip to a smaller military transport plane for a three-hour flight to the research station the US government operates near the South Pole.
Mr Kerry planned to visit that station for about two hours before returning to McMurdo for the night.
Mr Kerry's aides described the trip as a learning opportunity for the secretary of state. He planned to receive briefings from scientists working to understand the effects of climate change on Antarctica.
He has made climate change an intensive focus of American diplomacy during his term, and had previously spent decades working on the issue as a US senator.
He planned to return to New Zealand on Saturday.