3 1/2 stars. A highly enjoyable, thoroughly breezy piece of pop non-fiction for map nuts like myself. Brief, episodic chapters ensure that - if you're not gung ho on any given topic - you're sure to find a change in direction and speedy relief within a few pages. For myself, chapters on topics such as maps in video games didn't enthrall. But discussions of map thieves or treasure maps? Bring it on!
So why not 4 stars? A common gripe of mine - books about geography almost never have maps of suitable size and quality, and this one is no exception. Photos are frequent but are all black and white, often small, usually just details of a much larger work. Only in his end acknowledgements does the author note a few good web resources for looking at maps in their fuller glory, and most of these sites are already well known to map enthusiasts.
I would have loved if the author could have added notes in each chapter pointing to web images or resources, or perhaps created a web-based compendium of links for the entire book. Instead, I lost time on several goose chases; searching, for example, for a decent digital rendering of the Mappa Mundi (not available without paying £24 to Hereford Cathedral).