I've seen some discussion about the 101 yr old guy. Some wonder from the picture if he's really 101, but I'll assume it's true.
Last year he fended off a couple of muggers: FightingArts.com - The 100 Year Old Surprise
Calling him a "runner" may be a misnomer though. He recently finished a half-marathon in over 5:13. That's almost 24 minutes a mile. I walk pretty comfortably at about 20 minutes a mile, 15 or faster if I walk briskly. But I have seen other people running more slowly than I walk, so maybe he actually does run. If he's walking the whole thing, I prefer to see it called "finishing" a marathon, not "running" it. Just finishing will be quite an accomlishment for him.
Most marathons close their course after 6-8 hours because they can't keep streets closed that long, or volunteers out at water stops forever. For a case like this, I'm sure they'll make an exception and probably have someone escort him for safety, as it's going to take him at least 11 hours.