I just got
The Dictionary of Imaginary places today. This is my second copy, my first having been stolen by an ex girlfriend.
It is a reference book containing descriptions or locals from fantasy literature of the last two hundred years.
The book has descriptions of places from Abaton, a town that moves around the world and has never been visited, (described by Thomas Bulfinch in 1892) to Zuy, a elfin kingdom in the Netherlands. (described by Sylvia Townsend Warner in 1972)
The book is a great jumping off point for getting to know some great fiction you never would have stumbled across otherwise. For example if not for its description I never would have read
Titus Groan or
At the Earth's Core.
