Slipnir River

The Slipnir River is a river located on the border of modern-day (as of The Fifth Elephant) Istanzia. There were some issues with Istanzian troops launching incursions across it to attack whatever nation was on the other side, and the diplomatic corps of Ankh-Morpork was called upon to resolve the situation. Istanzia is bordered on The Discworld Mapp by two un-identified rivers. If the Slipnir is the southern one, the neighbour is one or mnore of Omnia, Betrek or Klatchistan. If the river is the nothern one, then the threatened state lies on the other side of the Morpork Mountains and the nearest two such are Chirm and then Ankh-Morpork itself. (the Morporkian Mountains open out onto the brassica-growing Sto Plains, although the Stos are apparently not on this side of Ankh-Morpork)

The Duke of Ankh, chosen representative of the city, warned the Istanzian ambassador that if these transgressions did not stop, the ambassador would be "going home in an ambulance". Since when not only have attacks across the river stopped, but the Istanzian army has withdrawn so far back that they are nearly in the next country. So if the Slipnir were to be the southern river, the logic of the situation dictates that the Istanzian army has regrouped almost on the border with Ankh-Morpork....