Nature is much more impressive that way than if it is overcrowded like Yosemite or Zion. I'll see if anyone else can recommend a book. If not, I'll have to rely on the recommendations at Amazon or another of the bigger online book stores. The only list I found was in a pull-down menu on Park Net . They seem to be booklets rather than books, but they are not very expensive, so I might order them to get an overview.
Members can request any number of tour guides and maps at no additional cost.
Their Tour Guides are excellent. The only problem is that since you live in Germany you might have a difficult time joining. My local chapter, Cincinnati , only allows people within Cincinnati to join. Jim, thanks for the idea. I got some maps and tour guides from the AAA from them.