suggestions for some other s-f books you might like.
The Doomsday Book and To Say Nothing of the Dog both by Connie Willis. About fifty years from now time travel has been invented/discovered (it's not clear or important which)and is controlled by historians who use it to go back and do research. In the first, a young woman is sent back to 1328 to a village in England. Things go awry. In the second, people go back to 19th century England to track down a piece of statuary. Things go comically awry.
A Bridge of Years by Robert Charles Wilson. Man buys an abandoned home in the pacific northwest and finds a door leading to a tunnel that ends in 1962 New York City. Why that tunnel is there is the rest of the novel.
Alternities by Michael P. Kube-McDowell. A man discovers a portal to an alternate world and uses it for his own ends.
Replay by Ken Grimwood. A forty-three year old man has a fatal heart attack, and suddenly finds himself back as his 18 year old self, able to remember the entire coming quarter century.
Time on My Hands by Peter Delacorte. A travel writer is given a time machine by a man who'd like him to use it to go back and keep Ronald Reagan from becoming president.
As you might guess, time travel is one of my favorite type of s-f, and these are especially good books that use it.
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