This thread caught my eye, and I've pondered what to say. I suspect none of us will beat BrianLe. It's one of those things that's so obvious it almost defies words.

Sometime around 1947 I discovered that for a cost I could afford, and by mail, I could get an index map from the USGS and then buy the quads for my area. It was like the whole world opened up.

I do not recall having even minutes of challenge trying to read them (other than looking up some symbols). They seemed self-explanatory.

The area where I lived (the Ozarks) was almost entirely forested at that time. Suddenly, I could tell where the mountains were, and even how high. Wow. The quads even showed where the streams ran, and where the springs were. Today I can't imagine being without that information in the woods. I've used "hiking maps" without that information and felt lost, even with the map in hand.

best, jcp