Free topo maps ... of just about anywhere in the U.S. This is another example of how modern technology has completely upended the old way of doing things. When I was a kid, if you wanted a topo map you either visited a musty old map store and hoped they had the one you wanted (out of the many thousands that were available), or you wrote away to a mail order firm and waited weeks or even months for your map to arrive. They weren't cheap, either. When you finally got your mitts on that map, it was a large piece of quality paper that had to be folded or rolled for transport. They were particularly awkward if you were hiking, and highly vulnerable to spoiling by getting wet or dirty. Usually we put them in a watertight plastic bag with the map folded so we could see the area around us without removing the map.
Fast forward to today. I haven't used a paper topo map for quite a few years now. My device of choice for map work is my iPad, but my iPhone works quite well, too. When I'm home I use my computer with its magnificent 27" screen. I can pan and zoom with the flick of a finger. And the maps got cheaper and cheaper, then free on certain web sites, and now – free to everyone through the USGS Store where you can download a PDF of any topo map for free.
It's an amazing world we live in...