Camilla went with a much more subdued hat choice than Zara, choosing a cosy-looking wide brimmed tan number.
She further accessorised with black leather gloves and a chiffon scarf, while a burgundy handbag added a pop of colour to the ensemble.
Camilla chose classic pearl earrings and a pale pink lipstick to add a touch of glamour to her outfit.
The Duchess – who owns a racehouse with her husband, Prince Charles – was flying solo at the event, as Charles was otherwise engaged at a reception celebrating frontline nursing in the UK.
It wasn’t the first royal outing at this year’s Cheltenham Festival. Zara attended the previous day’s races in a less formal get-up, choosing a green polo neck and black trousers paired with matching black ankle boots.
Her blossoming bump was covered by a black coat by WtR, while her bright red bag came from Paul Costelloe.
She finished off her look with a grey trilby by Goldust Millinery, and a pair of tortoise shell sunglasses.
Zara was joined by her mother, Princess Anne, who opted for a navy blue coat with a pale blue scarf, and a grey hat with feather detailing.