I forget when I last read this book. I seem to recall reading it several times during my early teens, but I've avoided it since. I'm not sure why - perhaps I was afraid it would disappoint. I've learnt to my cost that "nostalgia ain't what it used to be". Few books I loved as a teenager have survived a reread now that I'm just over halfway through my three score years and ten.
Having said that, I may well have not reread it simply because my To Be Read pile is big enough already. And continues to grow...
The novel won both the Hugo and Nebula Awards in 1971. It's also No 60 in the SF Masterworks series. So it's safe to say it's highly regarded by sf fans. But I'm not convinced sf novels stand the test of time as well as most fans would have us believe, and Ringworld is now 39 years old.
Everyone knows that the first edition had Earth rotating the wrong way - but this was corrected in subsequent editions. But there are other mistakes (in my 1981 Sphere paperback). On page 22, there is a description of the Long Shot: "The ship would carry practically no cargo, though it was over a mile in diameter." Yet when they finally see the ship: "The Long Shot was a transparent bubble over a thousand feet in diameter" (pg 46). The last time I looked, a mile was 5,280 feet. There's also a strange mix of metric and Imperial units: "The ring masses two times ten to the thirtieth power in grams, measures .95 times ten to the eighth power miles in radius, and something less than ten to the sixth power miles across." (pg 70). These are minor complaints, however.
Louis Wu is a 200-year-old adventurer in the 29th Century. He is recruited by Nessus, a Pierson's Puppeteer, for a mysterious mission. Also recruited are Speaker-to-Animals, a kzin, which is a large feline war-like alien; and Teela Brown, a young woman descended from five generations of winners of the Birthright Lotteries and so supposed to be very lucky. The mission requires a trip to an unspecified destination 200 light years from Earth. This would normally take several decades, but Nessus has use of a ship fitted with a secret "quantum II hyperdrive shunt", which travels orders of magnitude faster. This ship, the Long Shot, and the secret of its drive, will be Louis Wu and his team-mates' payment for the mission.
The team head for the home world of the Pierson Puppeteers... which proves to be a fleet of five worlds travelling through space at 80% of the speed of light. The puppeteers are a cowardly race and are fleeing the explosion of the galactic core, whose wavefront won't reach Known Space for another 20,000 years. Recently, they had discovered an artefact a couple of light years from their present position. A ringworld - a single band of material approximately one million miles in width and 600 million miles in circumference, orbiting one AU from its primary, and comprising the surface area of three million Earths. The puppeteers do not know who built the ringworld, and want Louis and the others to investigate it.
In a second ship provided by the puppeteers, Louis, Teela, Nessus and Speaker-to-Animals travel to the ringworld. While investigating one of the "shadow squares", which orbit nearer the sun and provde night and day on the ringworld, they are attacked by automated defences and crash on the ringworld's surface. They must then trek some 250,000 miles to the rim to seek help...
Niven's ringworld is one of the most famous Big Dumb Objects in science fiction. And justifiably so. It's huge. And Niven mostly succeeds in getting across its size to the reader. From the crash-site, for example, Louis can see for thousands of miles, but still can't make out the rim to either side. Compare that with Earth - on flat ground the horizon would be around three miles away for someone six feet tall.
And, I suppose, that if I'd forgotten anything about Ringworld, it was that sense of vast scale. Louis Wu is a protagonist very much in the mould of a US 1970s Competent Man. Teela Brown is decorative, screams a lot, and occasionally manages to surprise Louis with her perceptiveness and intelligence. He still refers to her as "my woman", however. The kzin is war-like, and the puppeteer is cowardly. Much of the universe of the novel, Known Space, was worked out in earlier novels and short stories. The prose is efficient at best, neither impeding the reading experience nor enhancing it.
The ringworld casts a huge shadow. It's the ringworld you remember when you close the book. It's the ringworld you remember decades later when you pick up the book to reread it. The rest is, well, just a story. The ringworld is sense of wonder. And if that's all you want in a science fiction novel, then you'll get it in Ringworld. If you're looking for more, you'll perhaps come away disappointed. Niven makes no attempt to explain the origin of the ringworld. The book's plot is little more than a trek to find a way off it. There are, I admit, one or two interesting sub-plots: for example, the puppeteers' meddling in both human history and kzin, the first to breed a "lucky" human and the second to make the kzin more docile; and the various speculations these revelations generate. Niven also manages to create a human but slightly off-kilter civilisation-in-ruins on the ringworld, although the name of one of its city, Zignamuclickclick, generates a wince.
I enjoyed my reread, but it did leave me somewhat dissatisfied. Not from the book's shortcomings - but because I'd forgotten how glibly sf writers of the 1970s used to make stuff up. They made very little effort to convince, they just waved their hands a little more vigorously. That's a style which is no longer in fashion. Science fiction in the 21st century is a far more rigorous genre, and it's better for it.
There are more novels following on from this one - The Ringworld Engineers, The Ringworld Throne, and Ringworld's Children - and these explain who built the ringworld, and why. I vaguely recall reading The Ringworld Engineers back in my teens, but I'll not bother this time. Nor have I any desire to read more of the series.
That's not, I hasten to add, because this first book in my 2009 Reading Challenge was a failure. On the contrary, it achieved pretty much what I expected it to achieve. I enjoyed the book, was reminded of some of the reasons why I'd liked it in the first place, and will someday no doubt read it again. But it's no great work of literature, and there are many science fiction novels I'd consider better than it.