St Piran's Day (Cornish: Gool Peran) is the national day of Cornwall, held on 5 March this year. The day is named after one of the patron saints of Cornwall, Saint Piran, who is also the patron saint of tin miners.
Legend says that Piran originated from Ireland, cast to sea tied to a millstone on the order of the Irish King who was suspicious of Piran’s miraculous powers. Piran survived stormy seas and arrived at Perranporth where he built an oratory to promote Christianity (his first disciples were said to be a badger, a fox and a bear).
The oratory is now preserved in the sand dunes at Perran Sands.St Piran's Day started as one of the many tinners' holidays observed by the tinminers of Cornwall. Other miners' holidays of a similar nature include Picrous Day and Chewidden Thursday.Patron Saint of Tinners
Piran is famous for his accidental discover of tin, when a black stone on his fireplace got so hot that a white liquid leaked out; the first tin smelting. It was this discoverey that earned Piran the title ‘Patron Saint of Tinners’, tin mining being the backbone of Cornish industry. This discovery also formed the basis of the Cornish flag, the white hot tin on the black of the ore.
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"St. Piran's Day was said to be a favourite with the tinners who having a tradition that some secrets regarding the manufacture of tin were communicated to their ancestors by that saint, they leave the manufacture to shift for itself for that day, and keep it as a holiday." There is little description of specific traditions associated with this day apart from the consumption of large amounts of alcohol and food during 'Perrantide'. The day following the St Piran's Day was known by many as 'Mazey Day', a term which has now been adopted by the revived Golowan festival in Penzance.