I want to know how big a large medieval city would be, considering a population of roughly 20.000. And by size I mean in terms of area or average diameter.
The real catch comes when the city is build in 5 layers on top of each other, so I'd assume roughly 1/5th of the size of a real medieval city here.
^ this was the actual question, more context on the situation below
It's a fantasy world in a custom D&D 5e world, comparable to medieval England~Germany around the high middle ages. Magic isn't rare here, it's rare enough that not every commoner has it, but common enough that magical beasts are used at war, or as pets of the rich.
The city in question is the capital city of the elves, and one of the largest, if not the largest, city on the mapped continent. It's the city of scholars, magic and, as far goes, science. Back to the catch: It's built between 7 large and ancient trees of 140~150 metres tall, the city is built:
- On seven silver bridges, where the royals live
- On a layer of wooden bridges, where most of schooling and art is done as well as military training
- On a second layer of wooden bridges, where most of the work-force happens (guilds, shops, etc)
- On a third layer of wooden bridges, where most of the commoners live
- On the forest floors, where the farmers live and a portion of the commoners.
I assume the agricultural level to be larger than the rest, but how large would this city span in terms of area / avg diameter otherwise?