Hundreds of people are expected to make the annual pilgrimage walk across Perranporth dunes to mark a saint honoured in Cornwall.
The march across the dunes is a highlight of St Piran's Day
It is believed St Piran landed at the dunes from Ireland and founded his first church there in the 6th Century.
Colliford Lake Park, Penwith, Newquay and Launceston Castle are also holding St Piran's Day festivities with Cornish song, dance and wrestling on Sunday.
St Piran is said to be the patron saint of once prosperous Cornish tin miners.
Cornish Lib Dem MP Dan Rogerson has tabled a Commons early day motion calling for the government to make 5 March a public holiday in Cornwall to recognise celebrations for St Piran's Day.
He said it was a "valuable opportunity" to celebrate Cornwall's unique heritage.