The event is being staged between 10am and 4pm on The Square in Market Harborough to pour money into the coffers of the Disasters Emergency Committee's Ukraine Appeal.
Talented local musicians will be performing all six hours while a bar, food outlets and craft and gift stalls will also be laid on.
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All of the cash raised will be donated to the new nationwide appeal – which has already generated a staggering £175 million.
All of the musicians are singing and playing for free and Harborough District Council are allowing the organisers to use The Square free of charge.
You can find out more about the Disasters Emergency Committee's Ukraine Appeal here: https://www.dec.org.uk/appeal/ukraine-humanitarian-appeal