Ringworld is probably Larry Niven's most famous work, having won both the Hugo and Nebula awards back in 1970 when it was first published. My previous experience with Niven's work, though, has left me cold. He's a hard science fiction writer and his characters have been very flat, to say the least. I hoped that Ringworld would be different.
It appears as though Niven had the idea for the ringworld and forced some characters and story together to give him a reason to write about the toy he'd invented. For me the result simply didn't work.
The toy itself - the ringworld - is an interesting idea, but other than some math about dimensions and spinning it to create gravity, everything else about it is pure, unadulterated fantasy. There are all kinds of impossible things going on here in the guise of "science": impossibly strong and thin wire, materials impervious to just about anything, multiple forms of FTL travel, unexplained failsafe systems, life extending substances, stasis fields, transmutation of one material into another, alien species, etc. One or even a few of these things would be fine in a science fiction work, particularly with some background and explanation, but Niven piles them up thick and just keeps going.
In short, he made up anything needed to let him talk about the idea of the ringworld itself. Everything other than the ring - characters, physics, story - was essentially superfluous. If he was a better writer I might have suspended disbelief, but that never happened. Not once.
Even worse, there were several places where the writing is so bad - or the copy I have is so poorly transcribed from the original - that after rereading a few paragraphs several times I had to give up and move on. Some things just didn't make sense at all.
In other places, despite the fact that the words and sentences held together, Niven didn't adequately describe the situation or action. After a while you just wind up accepting that he's not going to explain things well enough to make sense and forget about it. Not a good sign.
For amusement you can look it up on Wikipedia and read about other technical problems. There are quite a few.
I don't know why this book won any awards. It's not very good. My perception of Niven as a writer remains unchanged and I will avoid his work in the future. Too bad.