The summer spectacular has a host of fun-packed attractions to keep youngsters busy - including a large bouncy castle and soft play area with inflatable surround - as well as packed racecard.
There is also an appearance by children’s TV favourite, Fireman Sam.
Last year’s event attracted more than 5,000 people and a similar number is expected on Sunday - with Chad readers able to take advantage of a special two-for-one offer .
Nathan Corden, of Southwell Racecourse, said the event is always a hit.
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“This is the fourth year running that we have held the family fun day and it gets better every year,” he said.
“We have a vast array of entertainment and once you’re in the venue everything is free, all you need to do is present your two for one vouchers on the door. It should be a really good day and is a very safe environment where families can have fun together.”
Chad editor Tracy Powell said: “It’s a fantastic day out and excellent value for money, and we hope that many people will join us again this year.”
The first race starts at 1.40pm, with the last at 4.40pm. For more details of a two-for-one admission offer, see page 54.