I've seen a landscape map of nearby Leominster, Massachusetts, from the mid 19th century. All of the trees had been cleared for building and fuel and farming. In modern times, when the land is not farmed and the lumber is imported, many of those hills are once again covered with mature trees. You can see old stone walls, seemingly built through forest, but they used to mark the property lines of local farms.
In forests like this, you can get lost fifty yards from the trail. It's not unusual for bodies or even air crash sites to go unfound for decades only a few hundred feet from a road. I make it a point, when I leave a trail, to check my compass for the direction I'm going -- I don't want to get turned around and keep going that direction when I'm trying to return.
I like my old Lensmatic compass. I've used it for amateur mapmaking. However, it's a bit clunky for my backpacking; 2.2 ounces. I've replaced it with a key-fob compass, .4 ounces, that I wear comfortably round my neck on a lanyard.