Two blind adventurers are two-thirds of the way through a kayak descent of the Grand Canyon. Erik Weihenmayer is 'world famous' as an adventurer, according to his KayakingBlind.org website, so my apologies for not knowing who he is. He's joined by Lonnie Bedwell who is introduced in this video.
I came across them through watching some of the excellent Outside Online videos, in particular, this one. I spent some of last week being cut open as a surgeon repaired two hernias. I'm a bit sore and limited in what I can do for a few weeks, so I have plenty of time to trawl up stuff like this.