Mark, when you talk about the building on the causeway (there are several of them), are you referring to the ones that are attached to the long walls?
There are five structures attached to the long causeway walls in this section. You mentioned rounded cornices, so do you mean the tower on the top-middle of the causeway? If that's the right one, I don't think these are arcaded cornices. The rounded part extends above the top, which means it is more likely they are a form of merlon or roofing structure (but probably wooden rather than brick, since the brick ones were not rounded).
They're at the very top, in contrast to cornices, which always had a band between the arch shapes and the top. The tower is square, like the two shorter ones on the building on the right that faces the causeway and I think the color inside is for shading, just like the one facing the causeway (one is blue and one is amber like the one on the causeway).
There is also a larger drawing of a walled tower with Ghibelline merlons facing the causeway to the top-center rotum.
The building facing the causeway with the Ghibelline walled section and tall tower has a narrow saddleback roof (you have to look closely to see it), so it is more than likely the portal (the city gate) leading toward the top-right rosette since that's how they indicated city portals in the days of walled cities. Which means that the orientation of the entrance to the city would be from this causeway.
There are five structures attached to the long causeway walls in this section. You mentioned rounded cornices, so do you mean the tower on the top-middle of the causeway? If that's the right one, I don't think these are arcaded cornices. The rounded part extends above the top, which means it is more likely they are a form of merlon or roofing structure (but probably wooden rather than brick, since the brick ones were not rounded).
They're at the very top, in contrast to cornices, which always had a band between the arch shapes and the top. The tower is square, like the two shorter ones on the building on the right that faces the causeway and I think the color inside is for shading, just like the one facing the causeway (one is blue and one is amber like the one on the causeway).
There is also a larger drawing of a walled tower with Ghibelline merlons facing the causeway to the top-center rotum.
The building facing the causeway with the Ghibelline walled section and tall tower has a narrow saddleback roof (you have to look closely to see it), so it is more than likely the portal (the city gate) leading toward the top-right rosette since that's how they indicated city portals in the days of walled cities. Which means that the orientation of the entrance to the city would be from this causeway.