Two of the world's top female climbers are vying to become the first woman to conquer the world's 14 highest mountains.
The rivals and their teams are each preparing to make an assault on their final peaks - and either could win.
Spanish climber Edurne Pasaban has just one more climb to make after scaling a deadly Himalayan peak on Saturday.
But her chief rival, South Korea's Oh Eun-sun, is also on the slopes of her 14th mountain.
Competition between the two climbers is mounting in the final weeks of the race to scale all the world's peaks higher than 8,000m (26,250ft).
Climbing into history
Pasaban climbed one of the most lethal Himalayan peaks, Annapurna, on Saturday, leaving her with just one more to scale to become the first woman to bag all the world's 14 "eight-thousanders".
The 36-year-old Basque from northern Spain reached the top of the 8,091m mountain alongside several other Spanish climbers, a spokesman for her team told AFP news agency.
Only Tibet's daunting 8,027m Shisha Pangma stands between her and a place in climbing history.
However, Oh is now on the slopes of Annapurna, which would be her 14th and last summit. But the 8,091m peak is particularly dangerous, being both technically difficult and avalanche-prone.
It has a much higher death rate than Everest, the world's highest peak.
Oh, 44, is acclimatising at Base Camp Two on the mountain and expects to make an attempt on the summit on Saturday.
Oh currently seems to hold the advantage, although Annapurna, in Nepal, is the tougher climb. It has claimed 130 lives and has already defeated the South Korean, when she was forced to turn back in fog and blizzards last year.
Pasaban, who is single and has no children, also knows all about Annapurna: she was defeated once before, in 2007, when bad weather forced her and her team to turn back 1,000m from the summit.
If Pasaban wants to seal her place in the record books, she must hurry back down Annapurna and across the border into Tibet to begin her assault on Shisha Pangma early next month.
She will travel to Tibet to make her attempt "over the coming days", her spokesman said.
A third contender, Austria's Gerlinde Kaltenbrunner, is to begin her climb of the world's highest summit, Mount Everest, next week.
But she would still have to climb K2, the world's second highest peak, regarded as the most difficult and dangerous of the 14 summits, which all lie in the Himalayan and Karakoram ranges in Asia.
Italy's Reinhold Messner became the first man to climb all 14 mountains in 1986.