Does it have to be old to be a "classic"? If not, by far, One Hundred Years of Solitude by Marquez is my favorite novel by a Nobel winner. It's great, epic, and lovely to read. If you include epics, Mahabharata is actually a grand, epic book with war, friendship, love, sex, politics, realpolitik, strategy, and has a reach story line with scores of great side-stories. I also genuinely enjoyed Iliad and Aenied. I was also surprised at how good Candide by Voltaire was to read. Had a ton of fun reading it.
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