As the title says, carriages between towns that’s paid with gold. Aka system like in Skyrim.
The price would depend on your current weight and length between the destinations, not a fast travel system, but just speeds up the travel time between point A to B.
Maybe even add ambushes so that people wouldn’t go afk during the ride, pve/pvp ambush.
PVP would be kinda hard to implement, but i think pve is doable.