15thc perception on swallowtail merlons?

[MarcoP]

Here's an idea: maybe I should add castles which (almost) certainly had swallowtail merlons before 1450 to a separate layer?

Thank you Koen, this sounds like an excellent idea!
The Fenis Castle that David mentioned above can enter the list (You are not allowed to view links. Register or Login to view.).

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I suggest always adding the location when castles are mentioned: there are dozens of "castelli viscontei" / "castelli scaligeri" etc.