This one is not exactly a proposed outing, but it does sound interesting.
The Barkley Marathon is a 100 mile race that has taken place every year since 1986, and fewer than 10 people have ever finished it in the 60 hours allowed.
"The Barkley is considered one of the toughest 100 mile races in the world. It has 59,100 feet of climb (and 59,100 feet of descent), more than any other 100 mile race, more than the 33,000 ft. of climb at Hardrock, and more than the 45,000 ft. at Nolan's 14. "
"The course was designed by Gary Cantrell. His idea for the race was inspired upon hearing about Martin Luther King, Jr's assassin James Earl Ray escaping from prison, and making it only 8 miles (13 km) after running 55 hours in the woods. Cantrell said to himself "I could do at least 100 miles." Thus, the Barkley Marathon was born."
Wouldn't you know it. It is only about an hour from my house.
I'm not sayin I'd want to try 5 of those loops, but it might be a challenge to try one some time.
Anyone interested in a tough one? I'd say that hammock would be pretty darned comfortable if you can raise yourself enough to get in afterward.