Reddit mentions of Forest and Crag, A History of Hiking, Trail Blazing, and

The book Forest and Crag, by Laura and Guy Waterman, is exactly what you're looking for. It's mostly focused on the White Mountains, but it does have a few chapters devoted to the Adirondacks. It's an incredibly detailed and in depth history of hiking, camping, and backpacking in the northeast, covering over a century of recreational use. It goes into a lot of detail about the various issues that have cropped up over the years, including the boom of backcountry use in the 50's, 60's, and 70's that in turn lead to the development of things like Leave No Trace.

I'd also highly recommend two of the Waterman's other books on the subject of minimum impact hiking and camping- Backwoods Ethics (which deals with the issue of physical impacts), and Wilderness Ethics, which deals with the issue of social impacts.

I know that these are books and not websites, but there are kindle versions of each available as well.