The Peutinger Table is a medieval version of a Roman map that dates from the 4th or 5th century.
Scholars have long debated the map's purpose -- is it usable? merely decorative? -- and have contested how geographically accurate it is. As it survives, the map extends from the edge of continental Europe to the Indus river, where it is written "Hic Alexander responsum accept: 'Usque quo, Alexander?'" ("Here Alexander received the oracle: 'How far, Alexander?'"), and the map features symbols for cities, land features, and important sites.
Its extreme dimensions and skewed proportions -- roughly 22 feet long and 1 foot tall -- are confounding. Perhaps the Peutinger Table was rolled into a scroll which travelers used, or perhaps it was a display piece meant to advertise the magnificence of the Roman empire or the wonders of encyclopedic knowledge. We may even be missing the westernmost three segments of the map, which would extend to England and the mysterious Ultima Thule and position Rome at the map's exact center -- making the complete length 28 feet!
Further reading: http://www.cambridge.org/us/talbert/
http://upload.wikimedia.org/wikipedia/commons/5/50/TabulaPeutingeriana.jpg