"Licence for the dean and chapter of the church of Lincoln, for the security of the canons and ministers of their church, to enclose the entire precinct of their church and a certain lane between the dwelling places of certain canons of the church and the gardens of the said canons, which lane leads from the way of Estgate to Pottergate, and which the king had granted them a licence to enclose for the enlargement of the said dwelling places, and also the said gardens, with a stone wall twelve feet in height, and to crenellate the precinct, lane and gardens aforesaid, in accordance with a like licence granted to them by the late king on account of homicides and other outrages committed in the street and lanes around the precinct and in the precinct of their church."
Granted at Lincoln, by King.
The Dean and Chapter received licenses to crenellate the Cathedral. The first for a 12 foot wall (issued 1285 and repeated 1316) the second to raise the wall and add turrets (issued 1318). Some portions of wall and two towers remain.
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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