"Licence for the burgesses of Gernemuth to close their town with a wall and ditch so that the town shall remain closed so long as the burgesses remain faithful to the king and his heirs; and grant that there shall be a gaol in the town for the incarceration and keeping of prisoners and malefactors according to law and the custom of the realm."
Granted at St. Paul's, London.,
A grant of Murage for six years given at the same time.
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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