"Grant to the bailiffs and good men of Harwich, who intend to enclose the town with a wall of stone and to crenellate the wall, of murage for five years on things for sale coming by land or water to their town, or to the port of Erewell pertaining to the town."
Granted at Bury St. Edmunds, by King and Council.
Although this document has been considered by some as a licence to crenellate the current opinion rejects this as a licence to crenellate.
This reads like a murage grant to me but it is indexed as a licence to crenellate by the PRO.
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.)
More details about licences to crenellate can be found here.
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