The C.S. Lewis reference is interesting. He's obviously well-known for Narnia and for Christian Apologetics, but he also fits into the space/time travel category...

In the Chronicles of Narnia, the children mysteriously travel from England to Narnia through several methods (wardrobe, railway station, painting, etc.). Supposedly, you can't get there the same way each time. In the final book, the children arrive via a railroad crash (the books are set in the '40's, so that would be like an airplane crash today). Also, time in Narnia passes at a different rate than time in our world. The children return after 1 year in England to find that 100+ years in Narnia have passed.

And... in his Space Trilogy books, Space Travel and the battle between good & evil (in a strange land each time) are central themes.