Eternity Road by Jack McDevitt is a science fiction book originally published in 1997. The setting is the future USA after a plague has wiped out most of the population. All that is left of our 21st century civilization are artifacts, ruins, and the remains of our roads, thus the name "Roadmakers" is given to our civilization by the new emerging culture of city-states. There is a legend that some Roadmakers left a vast store of knowledge (books) in a place called Haven. The first expedition to fine Haven failed. A second expedition begins and much of the book covers this second expedition.
Eternity Road is not fine literature, but is certainly an acceptable science fiction yarn. There are better books out there about civilization ending, but this is enjoyable book to read for pleasure. There is no underlying theme or moral to the story. There is no epic battle of good against evil. It's more along the lines of an explorers travel log set in a different future. I'd recommend it.