Basically, the Peutinger Table was a picographic route finder for using Rome's highways. The famous copy we possess is 4th century, but older models were used in the 1st century. In the PT itself, the cartography was cartoonishly (and deliberately) painted askew, so that roads, cities and mileage data could all be fit together sequentially.
The new site is called Omnes Viae, and it remains absolutely the coolest thing I saw all day. Here's what the PT lists for an inclusive route Ab 'Athenas' ad 'Philippis'. The milage may not be 100% accurate, but it's accurate to what the PT said. And that's very interesting indeed.
H/T Deirdre Good, the Non-Sausage (on 9/7/11)
PS: Yes, I am enjoying getting caught up on my reader. Thank you, Google, again.