Jon Griffith and Andy Houseman have recently returned from Pakistan, having made the first ascent of Link Sar West, a subsidiary top of Link Sar with an altitude of just under 7,000m.
Lying close to the eastern end of the Pakistan Karakoram, the unclimbed Link Sar (7,041m) lies on the divide between the Charakusa and Kondus valleys.
The northern and eastern aspects of the peak rise from the Kondus and Kaberi glaciers, while the steep western and southern flanks lie above the head of the Charakusa.
Although steep, the most practical line from the Charakusa side lies on the northwest face, and leads to the western end of a one-kilometre-long ridge, a high point marked on maps as Pt 6,938m.
The highest point of the mountain, a mini Dent du Géant-like, snow-covered rock tower, sits at the eastern end of this technical, complex and corniced ridge.
Between 1974, when the Karakoram was re-opened, and the mid 1980s, when the Kondus side was closed due to the Indo-Pakistan conflict over the Siachen Glacier, Link Sar received its only attempt last century.
Kihuo Goto's Japanese expedition tried the east face above the Kondus Glacier, reaching ca 6,000m.
The Kondus re-opened briefly to climbers at the start of the new millennium, and in 2001 a strong team of Americans, including George Lowe and Steve Swenson, gained permission for another attempt.
The team made a reconnaissance of the Japanese line but found both it, and and alternative line to the left, far too dangerous. Subsequently, another attempt further right, and a later inspection of the north side of the mountain above the Kaberi Glacier showed similar problems.
All lines on this side appeared to be threatened by large serac barriers, some of which were not evident until at grips with the climb.
Before 2012 it would seem that no one had made a serious attempt on Link Sar from the Charakusa side. In that year Jon Griffith and Will Sim, on their first Himalayan expedition, attempted the northwest face, but dangerous amounts of unconsolidated snow, and altitude problems, forced them down.
Griffith returned for a second attempt the following summer with Andy Houseman but very hot weather and illness prevented much progress.
Undeterred by these setbacks Griffith enlisted American Kevin Mahoney for a third attempt in 2014. The two made a committing push and managed to complete the northwest face in awful weather.
They reached the ridge leading to the west top and got quite close, but too much fresh, bottomless snow on the very steep-sided crest caused them to take a serious re-think and make a wise but difficult retreat.
With commendable perseverance Griffith prepared for a fourth attempt in 2015 and Houseman needed little persuasion.
The two climbed the same line on the northwest face, but now aware of the difficulties on the steep-sided summit ridge, continued further up and left on the face to access the ridge at a higher point.
This still left a short section of awkward climbing but nothing like as bad as what Griffith and Mahoney had tried to deal with last year.
In mid July Griffith and Houseman made their first bivouac on the face at 6,100m, then waited there for a day to allow fresh snow to clear.
After a long hard day the pair reached the top of the face at around 6,800m, having climbed consistently steep ground, lots of black ice, and several mixed pitches up to M4.
That night Griffith came down with a fever and the two decided to stay put the following day.
On July 17th, with Griffith partially improved, they set off up the remaining ridge and by midday were standing on the 6,938m west top.
By this time they had run out of both food and weather window, and Griffith's fever was returning. Reaching the main summit was just impracticable.
They bivouacked close to the west top, and early next morning made a committing and blind descent of a couloir on the southwest face, which led to an unnamed glacier and down through a time-consuming icefall to reach the main Charakusa the same day.
They have named their ascent route Fever Pitch.
The pair deliberated, as no doubt will others, as to whether they reached a separate summit. Although it could not be defined as distinct, it dominates the west side of the mountain and is given a spot height on maps.
But as Houseman notes, ' Whether it is a true summit, an indiscriminate top, or nothing, we don't know, but having been there I feel it justifies being classed as a separate summit. Either way, we had an amazing adventure getting to it and back, and that's far more important'.
Don't want to miss out on the climbing competition action? Whether you're a competitor, spectator or volunteer, sign up to the climbing calendar mailing list to get reminders for comp registrations, and start times here.
JOIN THE BMC: Save 50% on your first year's membership
The BMC works for indoor climbers like you. Benefits include:
Access to BMC Travel Insurance
Register for Mountain Training award schemes
£10m worldwide Combined Liability insurance
£10,000 Personal Accident insurance
Discounted entry to many competitions
Find out more about BMC membership benefits
WATCH: Molly Thompson-Smith: Portrait of a Champion on BMC TV
Follow the BMC's competition climbing Twitter feed: @BMC_Comps
Find all upcoming competitions here.