There is a series, of course, that are a delightful mixture of mystery and adventure. They are set in the late 1800s in the glorious age of archeological discovery in Egypt and the surrounding areas. The author is Elizabeth Peters and the books are the Amelia Peabody mysteries.
Along the lines of fantasy or science fiction there is another series of books called The Dark is Rising by Susan Cooper. These books have been around for a while and they even made a movie about them, though it doesn't follow the books quite as well as I would like.
These books follow a young man who discovers that he has some magical gifts and he must find certain signs and bring them together to fight the rising dark. It is fantasy all the way, but if you like Arthurean legends and stuff like that then you will enjoy these books as well.
So those are my suggestions for today. Enjoy