"abbathiam beatae Mariae quod ipsi abbathiam suam praedictam extra civiatem nostram Ebor. eidem civitati contiguam muro de petra et calce in solo suo proprio pro suo libito firmare et kernelare. Ita tamen quod murus inter dictam abbathiam et murum civitatis praedictae per ipsos abbatem et conventum constructus vel construendus sexdecim pedes in altitudine non excedat nec etiam kernelletur, &c."
Granted at Northampton, by King.
The licence has unusual restrictions clearly showing the concern of the citizen of York and the effect this fortification had on their town wall.
Original source is
(In fact, the original source given is usually a transcription/translation of what are precious medieval documents not readily availably. It should be noted that these transcription/translations often date to the nineteenth or early twentieth centuries and that unwitting bias of transcribers may affect the translation. Care should also be taken to avoid giving modern meaning to the medieval use of certain stock words and terms.)
Significant later source are;
More details about licences to crenellate can be found here.
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