Monaco's Prince Albert has swapped the sunshine in his glamorous Mediterranean principality for the frozen Arctic as he attempts to trek to the North Pole.
Prince Albert was sworn in as Monaco's ruler last July
The 48-year-old prince and his team of seven are making the 57-mile (92km) journey on dog-pulled sledges.
The prince says he is using the trip to raise awareness of the dangers of global warming.
The trip will also pay tribute to his great-great-grandfather, Prince Albert I, who made a similar trek in 1906.
"Prince Albert is in excellent form, full of energy and aiming for victory," trip co-ordinator Dmitry Shparo told the AFP news agency.
He said the team, which left the Russian tent camp of Barneo on Thursday, hoped to reach its destination on Sunday.
As well as extreme cold and strong winds, the expedition is expecting to face polar bears, drifting ice and "ice that can pile up several meters which is hard to get over with dogs and heavy sledges", the prince's website says.
Prince Albert was first flown in a Boeing Business jet from Sweden to the Norwegian outpost of Svalbard, and then by a twin-jet Russian Antonov-74 to a makeshift landing strip at Barneo, AFP reports.
Twice-daily hot meals for the team have been prepared from the kitchen of world-famous chef Alain Ducasse, a spokeswoman was quoted as saying.
Prince Albert assumed the throne of the tiny tax haven on France's Riviera last year after the death of his father, Prince Rainier.
His ancestor Prince Albert I made four Arctic expeditions a century ago.