Road station
Ad Fines
Pfyn SWI
At Pfyn in the Swiss canton of Thurgau, substantial remains of a late Roman fort of the fourth century survive beside the road from Winterthur to Arbon on Lake Constance. Here the province of Upper Germany met Raetia, and the map's reckoning changes too: from here on, distances are counted in Roman miles instead of Gallic leagues. Even so, it is unclear which unit the twenty-one on to Arbor Felix means, since the real distance is at least twenty-five miles. The name Ad Fines, At the Border, is shared by several other places on the map.