A great book I've recently enjoyed reading is a Stephen King book called 11.22.63. Its a time travel story about a guy named Jake who's dying friend shows him a gateway to the past, that just happens to be in the back of his restaurant's pantry. The time portal or rabbit hole, as it is referred to in the book, always takes you back in time to the same day in 1958. Every time you go down the rabbit hole you reset anything you did on your last trip. Jake's dying friend Al asked him to try and finish the job he started and stop the assassination of John F Kennedy. Al has lived in the past for 4 years, until 62, but returns to the present when he is diagnosed with cancer. He has collected lots of notes and hands them over to Jake. Al is convinced by stopping JFK's death that a chain of events would happen making the world a better place. The question is will Jake go back and wait 5 years to stop the presidents death?
Very minor spoiler ahead, just in case you every read it...
Its a great read. I really felt like I was going to 58 with Jake, on each trip he took

That's not really giving much of the plot away.
At times the story gets wrapped up in a lot of facts that King has included about a certain gunman that had some involvement. But the heart of the story, is really about Jakes journey into the land of long ago and the choices he makes and the people he meets along the way to his ultimate decision. Definitely worth a read if you like a good time travel story.
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