Organisers hope that around £2.5million will exchange hands at the Kelso Ram Sales.
More than 5000 rams have been entered for sale.
It's the 175th year of the famous sales, organised by the Border Union Agricultural Society.
"It has just grown with tradition over all these years and it actually has become the barometer sale of commercial ram sales for possibly the whole of the UK. I always say to everyone I know they should always experience the ram sales once, it is unique."
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