Writing for "The Sunday Times", the fourth in line to British throne explains how his experiences at war had sparked his desire to organise the Invictus Games.
"Sure, I'd heard about it, expected it, called in many medical evacuations for it, but I had never seen it first-hand," writes the 29-year-old prince.
"By 'it' I mean the injuries that were being sustained largely due to Improvised explosive devices. Loss of life is as tragic and devastating as it gets, but to see young lads - much younger than me - wrapped in plastic and missing limbs, with hundreds of tubes coming out of them, was something I never prepared myself for. For me, this is where it all started," Harry added.
The Royal regularly flew injured personnel and civilians to the hospital at the Camp Bastion military base during his second tour of the country when he served as an Apache helicopter pilot.
More From This Section
"Many of us who have been on operations can close our eyes at any point now and hundreds of images will flash through our minds, a visual diary of our experiences. But I really can't imagine what it must be like to have images of friends - lost or wounded - move across your mind like a bloody slideshow," he said.
The Invictus games - aiming to showcase the bravery and sporting prowess of more than 400 servicemen and women from 14 countries who have been left wounded by war - will take place next month at London's Olympic park.