Winnie the Pooh drew the map of the 100 Aker Wood on his book (Mr. Shepard helped), which has been loved to cracking by my family for years, and is the first book I remember with a map. As a child a map at the beginning of a book was an invitation to adventure for me, and a guaranteed read.
If maps on the inside covers of a book tickle your fancy too, check out this link. It includes this map, in a book by Arthur Ransome, who included maps in most of his work. The maps visualized the adventure you were about to embark on, often with comments by the characters. Check out more of them here.
How about you? Do you remember books with maps?