Route: Northville - Lake Placid Trail (NY)
According to Wikipedia: "The Northville-Lake Placid Trail, also known as the NPT, is a lightly-travelled foot trail that runs 133 mi (214 km) through the Adirondack Park in northern New York State. It was laid out by the Adirondack Mountain Club in 1922 and 1923, and is now maintained by the New York State Department of Environmental Conservation."
Though the NPT is officially 133 miles, for 10+ miles from Northville to Benson it follows paved roads, and the last 1.2 miles or so into Lake Placid are also on paved roads. Most hikers consider the "practical" end points of the NPT avoid these beginning and ending road sections, so that the trail route is about 122 miles. So far, speed runs of the NPT have also skipped these beginning and ending road sections.
Prior to Tim Seaver's 2005 run, Richard Denker held the FKT for the NPT at 40h20m, set in August 16-17, 1973, when Denker was just 18 years old. He was supported by a large group from the Boy Scouts of America.
Vermonter Tim Seaver broke Denker's record on August 6-7, 2005, running 122 miles in 37h31m, supported by his wife and a friend, and using about 44 self-cached 1/2 liter water bottles. Seaver had posted his own splits, as well as details of Denker's 1973 run, on his website, but this information seems now to have disappeared. Seaver did discuss differences between the route of the trail in 2005 and 1973 on the Adirondack Hiking Forum, but again this seems to be gone. It appears that Seaver's run was about 2 miles longer than Denker's.
Sheryl Wheeler ran the 122 mile trail section in 35h13m on June 15-16, 2011. This is the overall FKT. She also ran the entire 133-mile Northville - Lake Placid Trail in a time of 39h16m. This was a supported run, but we have no further details.
There have been a couple fairly fast unsupported trips on the NPT. Drew Haas did the full 133 (135?) miles from Northville to the Averyville Road train station in 2d12h30m on Sept. 2-5, 2009, Previously the fastest known unsupported time was 3d8h by Erik Schlimmer, in October 2008.