Below 'Iter vestrum' (latin for 'Your trip') enter an 'ab' (from) and 'ad' (to) name as can be found on the Peutinger map (or in the Itinerarium Antonini for the westernmost area). For some cities current day names are understood. Mind that often a 'v' character is used instead of the expected 'u' and similarly for the 'i' and 'j'.
Click 'Ostendere' ('Show') to have to shortest route ('Iter brevissimum') displayed.
Try for example 'London' and 'Pompei' or 'Aquae Sulis' and 'Roma'. The route will be shown as can be found on the Peutinger map.
Looking for Roman history nearby?
Tabula Peutingeriana and Itinerarium Antonini