When we first moved out of my childhood home, I did not want to visit it again, it was old and dirty and the paint was peeling and the floors were cracked and then it was a few years later that I couldn't visit it anymore, I think it was turned into a shopping complex. What I wouldn't give to walk through that house again. In my dreams, when I'm at home, it's always that home.
This book reads like a fairytale for adults. I guess that's what Gaiman is a master of. Our unnamed protagonist visits a pond that a friend considered the ocean and as he sits there, the waves of his childhood memories wash over him and the rest of the story is from his 7-year-old perspective.
If we return to artifacts of childhood memories, everything is smaller, lesser than we had imagined. Things don't taste as good as that memory did. But every so often, the wonder holds up. An ocean turns out to be a duck pond but maybe it really was the ocean after all.