Because, it is the ultra-close-ups where you do the actual drawing!
Unlike the old VN maps, when space runs out, we won't simply expand the map.
Rather, it will be made of countless single maps, split up further.
Here is the city map.
NOW is the time to edit, though keep edits more general, as each section will be split up further.
Use the smallest and second smallest line tools and add roads to sections. Each section should have a theme, something either found in a city, found in GD, or both.
The largest, slightly to the right of the middle, is reserved for government constructions.
Do not put too much detail in yet. Maybe draw the individual buildings, but do not overdecorate them. Once a section is fully complete, it will undergo a single X4 zoom, and THEN you add the real details.
FYI the zoom levels are 4x4x8, for a total of 128x the main map. And then another x4, for 512x.
And then, you may create a local map of your property, if you *really* wanted, at a higher zoom than that...
Do you really think that you can draw a whole 512x512 square in a single pixel? I don't think so. THAT is why the map is reduced first!
Cthulhu's cave is 22 pixels high on the main map. Do you think he needs a 11264 pixel high drawing area? Not really.