"Cimiterium ecclesiae Cathedralis Wellen. et procinctum domorum suarum et Canonicorum infra civitatem Wellen. muro lapideo circumquaque includere et murum illum kernellare batellare ac turres ibidem facere
Licence, for the glory of God, the honour of the cathedral church of Wells and the saints whose bodies repose therein, and the security and quiet of the canons and ministers resident there, for Ralph, bishop of Bath and Wells to build a wall round the churchyard and the precinct of the houses of him and canons, and to crenellate and make towers in such wall. He is to make doors and posterns in the wall where necessary, and to cause any streets enclosed to be diverted in such manner as shall be most to the public convenience, and the doors and posterns to be open for thoroughfare from dawn till night."
Granted at Westminster, by privy seal.
This licence was for the palace and close, but the current palace is the main result of this licence.
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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