It seems like it could look good. Also, they could stop expanding with new districts which would show a clear limit between the old town and new town.

It's weird to see the walls go away in the first turn of that era but there's no wall in our modern era too.

Valmighty wrote:

It's weird to see the walls go away in the first turn of that era but there's no wall in our modern era too.

It's actually not that rare to have modern cities with remnants of roman or medieval walls.

I agree, the walls should stay visible where they were, and new districts not having walls.

I find it bizarre that the walls disappear. IMHO, it would be much better if they simply stopped expanding around new districts as previously suggested.

Valmighty wrote:

It's weird to see the walls go away in the first turn of that era but there's no wall in our modern era too.

Ignoring the fact Undernier is talking about historical walls, that you can find in multiple cities all over the world.
The Berlin Wall? The Peace Lines/Walls in the Irelands? Israeli West Bank barrier? The Kabul Airport Walls seem pretty relevant these days too.

I dunno, I would say we do have walls in our modern era

I would love to see walls on parts of "old city" in modern era, as suggested.