A group of Army mountaineers are attempting to be the first Britons to climb Mt Everest via the West Ridge, the Army says.
The Army says only 13 people have ascended using the West Ridge
If successful, the ascent would be an "historic first for Great Britain," it said ahead of the climbers' May ascent.
Twenty-one men and women will scale about 29,029ft (8848m) - an effort only completed by 13 people.
It coincides with the 30th anniversary of the Army Mountaineering Association's summit of Everest.
The first ascent of the Everest West Ridge was in 1963 by Americans Willi Unsoeld and Tom Hornbein.
The British Army attempt is to test planning, preparation, training and team skills.
Three climbing teams will climb three routes in and around Mt Everest, including a team of "highly-experienced cold climate, high altitude mountaineers".
They will leave for Tibet on 22 March and expect to reach the summit in May.
"We want to make British history," said Warrant Officer Dave Bunting, a veteran of nine Himalayan expeditions with over 20 years experience in the Army.
A team of intermediate level mountaineers will climb the nearby 7,045m Lhakpa Ri peak, while a third team of "raw recruits", aged 16-17, will climb Island Peak's 6,250m.