Among the letters is one to his wife where he sums up the odds of reaching Everest s summit - "50 to 1 against us", he says, not knowing that the world s highest mountain would go on to claim his life.
The mountaineer and explorer was 37 years old when he and his climbing partner Andrew Irvine vanished close to the summit of the highest mountain in the world.
Letters from the British climber George Mallory, who disappeared on Mount Everest in 1924, to his wife Ruth have been published online by his former Cambridge University college.