Well, the name of the world and its regions are 'made up' so phooey on that rule... And I think I'll use bullet points
The world I use for my campaign is the the world re-skined. In this way I can use google maps to plot routes and distances. I have pre-made terrain features by default. If I need to make some changes then I do. Like, if such and such a mountain is only 3500 ft tall, well... maybe it sounds more majestic at 8500 ft.
The campaign starts in a commonwealth/Alliance of states that includes
a cosmopolitan republic with the world's largest city (30,000 People or so). (Montreal)
A Rohan/Poland inspired coastal plains defended by mounted lancers that are based on Hussaria (Boston)
The Halfling city that is a protectorate of the Coastal Plains state (Providence, Rhode Island)
An ancient Elven, post-scarcity city-state, utopia that only Elves can enter (national park in New Hampshire)
The last remaining Mountain Dwarf Stronghold on the continent. (Southern tip of the Green Mountain range in Vermont)
An island nation ruled by a monarchy that used to have a vast mercantile empire, fell into decline, but is rebounding as he commonwealth's premier shipbuilders. (Newfoundland)
A Norse inspired Northland where Humans, Hill Dwarves and Half-Orcs live under a covenant of fraternity. (Far North in Quebec & Labrador)
Hobgoblins have twin Strongholds in Baltimore & Washington DC
PCs smashed a Hobgoblin Camp set up in Allentown Pennsylvania
The 'enemy' nation is located in Florida (Mordor w/ Palm trees)
Dinosaur Island is located in Cuba
Denali state national park in Alaska hosts the grandest of all fallen Dwarven Fortresses
Mount Mitchel in North Carolina hosts a Dwarven Stronghold that the PCs are planning on exploring the following spring.