Heraldry
The Roman military decoration came to be employed in European heraldry, where the term is used to denote a crown modeled after the walls of a castle, which may be tinctured or, argent, gules, or proper, i.e. stone-coloured. In Germany, during the 19th century mural crowns (Mauerkronen) came to be adopted for the arms of cities, with increasingly specific details: "Residential (i.e. having a royal residence) cities and capital towns usually bear a Mauerkrone with five towers, large towns one with four towers, smaller towns one with three", observed Arthur Charles Fox-Davies, in A Complete Guide to Heraldry, adding "Strict regulations in the matter do not yet exist" and warning that the usage was not British.
In recent times, mural crowns used, rather than royal crowns, for Italian medieval and modern communes. A mural-crowned lady, Italia Turrita, is a symbol of Italy. In Italy, communes and some provinces and military corps have a mural crown on their coat of arms, golden and with five towers for cities, silver and nine-towered for the others; also use it. The coat of arms of the Second Spanish Republic had a mural crown. Most Portuguese (and Brazilian) municipal coats of arms contain a mural crown, with three towers in modern usage signifying a village, four towers representing a town, and five towers standing for a city. The Romanian municipal coats of arms contain a mural crown, with one or three towers for villages and communes, five and seven towers for towns and municipalities.
After the dissolution of the Austro-Hungarian Empire at the end of World War I, the single-headed eagle of the coat of arms of Republic of Austria began to wear a mural crown in the place of the former royal Austrian and Hungarian crowns that adorned the double-headed eagle of former coat of arms.
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