Pretty self explanatory, I am wondering how many people a traveler may have enountered while traveling on ancient Roman roads. I picked Rome -> Athens as an example but the destination can be different if need be.
This is sort of dodging the question (and as it is written I'm not sure if I could answer it), but why would anyone travel on foot from Rome to Athens? Traveling and shipping cargo by sea was vastly cheaper, safer, and faster even for relatively short distances. Certainly for a journey like that from Athens to Rome, in which travel by foot would vastly increase the distance traveled, sea travel would be by far the more common and intelligent option