The odd sort of thing that I choose as unchallenging bedtime reading. Obviously a bit out of date (I chuckled at the passing reference speculating whether we might be entering a new ice age... oh yeah, 1980, they were still speculating about that in the 1970s) and I wonder how much has changed regarding many of the interpretations, but still an intriguing read to get some regional geology background. I've got a lot of Wyoming to explore before I start on Colorado, but this has definitely got me excited about that as well.
Bonus points if you've listened to any amount of C.W. McCall because you'll recognize a lot of place names from "Wolf Creek Pass" and "The Galloping Goose" and "Four Wheel Cowboy" and others I've either not listened to or have forgotten at the moment.
And of course you can't beat that last name. "The Chronic."