Prince William completed his final shift as a pilot with the East Anglian Air Ambulance on Thursday.
The Duke of Cambridge, 35, is stepping down to take on more royal duties on behalf of his grandmother, Queen Elizabeth, and his grandfather, Prince Philip, who announced he was retiring from public engagements starting this fall.
William marked the occasion with a letter reflecting on his two years with the EEAA, which he joined in 2015 after flying rescue helicopters with the Royal Air Force.
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"Over the past two years I have met people from across the region who were in the most desperate of circumstances," William wrote in a letter published by the Eastern Daily Press. "As part of the team, I have been invited into people's homes to share moments of extreme emotion, from relief that we have given someone a fighting chance, to profound grief. I have watched as incredibly skilled doctors and paramedics have saved people's lives."
"These experiences have instilled in me a profound respect for the men and women who serve in our emergency services, which I hope to continue to champion even as I leave the profession," he continued. "I am hugely grateful for having had this experience."
William also recalled some of the heartbreaking experiences he's had on the job.
"One of the first call outs I made was to a young man who had taken his own life; it was an incredibly tough day and had a profound effect on all of us, not least in my determination now to draw attention to this issue," he wrote. "Another rescue that sticks in my mind was to a young man who was involved in a road accident. His uncle in the car with him sadly didn’t survive, and I was sure that from what we were faced with he wouldn’t either – but thanks to the skills of our medical team he is alive today."
"I now know though that there are things that cannot be unseen and experiences that our first responders deal with on a daily basis that they will carry with them for life," he added. "As I hang up my flight suit, I am proud to have served with such an incredible team of people, who save lives across the region every day."
Last December, Queen Elizabeth, 91, announced she was taking a step back from her royal duties -- stepping down as patron of 25 organizations -- in order to reduce her workload. She handed over her patronage of certain groups to other members of the royal family, including William, Kate Middleton and Prince Harry.
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William and Harry recently revealed the last conversation they had with their late mother, Princess Diana, in HBO's new documentary, Diana, Our Mother: Her Life and Legacy.