Kings Lynn (Lynn {Lenn}) was given a grant of murage dated 10/7/1338.
This was in the form of:-
Wording
Appointment, after security found by them before the king, of the mayor and burgesses of the town of Lynn to the custody of their town, during pleasure, to preserve it against attacks of enemies, with power to levy a subsidy on those dwelling within the town according to their ability for their defence; without prejudice to liberties granted to A. bishop of Norwich or his predecessors by royal charters. By K.
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May 4. 1377. Westminster. 51 Edward III.
Inspeximus and confirmation to the mayor and burgesses of Lenn of letters patent, dated at Walton, 10 July, 12 Edward II (rectius III), in their favour. {Calendar of Patent Rolls, 1338-1340, p. 110.}
For 1 mark paid in the hanaper
Granted by Edward III. (Regnal year 12). Granted at Walton. Granted by K..
Details of the petition which resulted in this grant can be seen
at this link. 
Primary Sources
Maxwell Lyte, H.C. (ed), 1898,
Calendar of Patent Rolls Edward III (1338-40) Vol. 4 p. 110
online copyMaxwell Lyte, H.C. (ed), 1916,
Calendar of Patent Rolls Edward III (1374-77) Vol. 16 p. 459
online copy
Secondary Sources
Turner, H.L., 1971, Town Defences in England and Wales (London) p. 129
Comments
The Inspeximus presumably because of some challenge to a levy that would, by then, have been in force for nearly 40 years. The confirmation must have made this levy basically vested. It should be noted walls are not mentioned and this levy may have (also) covered the cost of watchmen and repair, replacement and maintenance of equipment for the towns defence, such as bows and arrows.
Record created by Philip Davis. This record created 25/01/2009. Last updated on 04/05/2012. First published online 5/01/2013.
