I like what This Immortal by Roger Zelazny was trying to do and in many ways it succeeds. This is the myth of the Greeks in science fiction form. A story of a trip traveling through many hardships and strange places and finally returning home changed. I even enjoyed it most of the time. That said, this book did not deserve the Hugo. The problem is of course that it tied with a considerably better book Dune. Still, it did win and it is worth examining.
The story takes place on earth after The Three Days, which was presumably a nuclear war. The Vegans arrived on earth and saved most of what was left of humanity leaving only a few people behind mostly as tour guides. This story takes place long after that with a character who has a special talent you might gather from the title of the book. Beyond simply being This Immortal though Conrad is also skilled at a lot of different things which makes some sense and has in the past formed one of the political groups which are struggled to bring humans back to earth as well as keeping it out control of the Vegans.
He is pushed into taking a visiting Vegan on a tour of a number of locations on earth many of which are quite dangerous because of the mutated animals. In addition there are strong suggestions that someone with him is trying to kill the Vegan.
The story feels a bit disjointed as it cuts from one adventure to another with very little really connecting them. This is at least partially intentional I suspect as many of the myths that this uses well have this style. The writing in This Immortal also feels a bit stilted at time, but this is also by design of the style I believe.
The end of this story felt as if it were supposed to be a surprise but the truth is that it really did not feel all that surprising but in large part the story not about the ending it is about a style and the modern myth.
If you are going to read one book from 1966 then I suggest Dune as it is not only a far more famous book, but one that tells a better story. Still if you love myths and especially Greek myths such as the Iliad and the Odyssey and the stories of the Greek gods then you should really enjoy this story.