Before Ian's death, Matt Blank, his climbing and BASE jumping partner, wrote letters to all of his friends and family in case of his own hypothetical death. One of the letters was to Ian.
In this video - produced by GoPro - Matt reads out the letter he wrote to Ian before he passed away. It's heartbreakingly touching and sad to hear how much he valued his best friend Ian.
"You either live a genuine life that's true to who you are - or you don't"
As Matt says: "How can you express everything that you want to somebody you love, knowing that if you don't, that might be the last opportunity that you have?"
While BASE jumping is an inherently dangerous sports, both athletes knew the risk and embraced their passion for living life to the limit.
It's a really touching tribute, watch the full video below.