On Friday, while I was translating the chapter on the history of mapmaking ('Here Be Dragons'), I found out that Wikipedia has a super hi-res picture of the Tabula Peutingeriana. As a fan of both visual displays of information and of ancient and medieval history (particularly the transition period between the two, the 'Dark Ages'), I couldn't help but fell prey of nerdy ecstatic joy. The Tabula is a copy of a copy of a road map of the Roman Empire, and it's structure and design rationale reminds me of modern node-based charts, such as Henry Beck's London Underground Map.
I realized that I had read about the Tabula just in two or three histories of Mapmaking, such as this, and this. So I went to Amazon.com and did a basic search. I found a couple of books that look interesting: Rome's World and Travel in the Ancient World. I may take a look at them soon. I am already thinking about what my next book is going to be about, and the Tabula may enjoy a special place in it.