Two teenagers hoping to become the youngest Britons to climb Everest have begun their final hike to the summit.
The pair spent time acclimatising themselves to the altitude
School friends Rob Gauntlett, of Petworth, Sussex, and James Hooper, of Wellington, Somerset, both 19, spent two years planning their epic trek.
They celebrated Rob's birthday at Everest Base Camp on Wednesday, and on Saturday struck out on the last section of their journey to the top.
Weather permitting, they hope to reach the 29,035ft (8850m) peak on Wednesday.
Earlier this year they feared they might have to abandon their attempt after failing to raise enough sponsorship money.
But a last-minute wave of support meant they were able to fly out to Nepal at the beginning of April, and have since spent the past six weeks acclimatising to the harsh conditions.
By reaching the peak and breaking the record, James and Rob hope to raise £1m for Cancer Research UK.
James said: "I will put every last grain of energy I have into reaching the top and returning safely, not just for my own adventurous spirit but for the whole team that have undertaken this challenge with us."
The record for the youngest Briton to climb Everest is currently held by Jake Meyer, 21, of Tetbury, Gloucestershire, who managed the climb in June 2005.
The youngest person to reach the summit was 15-year-old Ming Kipa Sherpa, who completed the ascent in 2003.