1578: An Arch on the Plan of Barcelona

We have this 1567-1578 plan of Barcelona with a bizarre arch in the right top corner. I believe the image was a part of the Civitates Orbis Terrarum atlas.
  • Any ideas what this arch could be?
  • Also, do you have any idea what kind of ships could be entering through that arch?
1567-arch-1.jpg


Full Image
1567-Barcelona_1.jpg

Any help with the translation would be appreciated.

1567-Barcelona_description.jpg

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