This is a extraordinary tool developed by Stanford University: Orbis. Select place of origin, destination and season of the year and you will know how many days were necessary, and the cost, to make an specific travel during the Roman Empire. Needless to say that I am using it when writing my long and neverending Roman times fanfic.
This is amazing! I can use it 🙂
Indeed it is. They have improved lately the graphics… it is the manna of a lazy writer like myself 🙂