Guiding Dan Berlin in the California International Marathon

I'm in Sacramento, California to guide my friend Dan Berlin in the California International Marathon on Sunday, December 7. Dan steadily lost his sight over many years due to the disease cone rod dystrophy. But he didn't let blindness stop him from becoming a marathoner and triathlete. I served as his guide two months ago when he became the first blind runner to cross the Grand Canyon and back nonstop. That feat has generated a lot of press, including a story on CBS Evening News (see pics below).

This will be the third time I've guided Dan in a marathon. We also did a 1/2 Ironman together last year. We were tethered together on the 1.2-mile swim, rode a tandem bicycle on the 56-mile bike portion and held a tether between us on the 13.1-mile run. And we'll run the Boston Marathon together on April 20, 2015. He's in remarkable shape and always up for an endurance challenge. There's more to come!

Scott Pelley introduces the story about Dan Berlin

Dan being interviewed by Barry Petersen, one of CBS's most experienced correspondents 

In this photo, I'm helping Dan cross a stream in the Grand Canyon with assistance from fellow guides Alison Qualter-Berna and Pete Kardasis