Let's say that you've been transported back in time to the Second Century A.D. You're in Eburacum, a Roman fort located in what is now Barnsley, South Yorkshire, UK. You want to get Tanais, which is a Greco-Roman colony at the mouth of the Don River in what is now Russia. How do you get there?
Google Maps isn't going to help you. But ORBIS will. Provided that you can get a good WiFi signal, you can pull up this complex mapping and travel planning program from Stanford University.
ORBIS comes with many different options to help you select your route. You chose to go as fast as you could, by any means possible, and during the summer. Well, you didn't hire a horse relay--you're not made of denarri. But you did rent horses for the journey.
You're throwing a lot of money at this problem, but it's still going to take you a long time to get from England to Russia compared to modern standards. You're riding horses over what is now southern France, central Italy, and Serbia. You're also traveling by ship and riverboat. The trip will take you more than 60 days.
If you don't have a lot of money available, then you may have to travel by foot and slower sea-going vessels. Then the trip will take almost 84 days.
ORBIS is fun! You can explore it here.
-via Marginal Revolution