Kate Middleton stepped out in style for her first royal engagement after giving birth to her third child — in a trusty pair of 14-year-old riding boots.

On Tuesday, the Duchess of Cambridge arrived at the Sayers Croft Forest School and Wildlife Garden in west London looking chic and casual in an olive green sweater with matching jacket, light brown skinny jeans, and her go-to Penelope Chilvers Long Tassel Boots, which retail for $617.

Kate, Duchess of Cambridge, arrives at the Sayers Croft Forest School and Wildlife Garden at Paddington Recreation Ground, London, Oct. 2, 2018. 

Kate, Duchess of Cambridge, arrives at the Sayers Croft Forest School and Wildlife Garden at Paddington Recreation Ground, London, Oct. 2, 2018.  (AP)

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According to People, the 36-year-old royal first wore the boots in 2004, and has donned them for many outdoorsy royal appearances since, including trips to the Himalayas and Canada.

The 36-year-old royal first wore the boots in 2004.<br>
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The 36-year-old royal first wore the boots in 2004.
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(Getty)

“It’s great to see the Duchess wearing the first boots we made for her in 2004 – 10 years on,” Chilvers told the outlet in 2016 of her famous fan. “The boots only get better with age. She looks fabulous in them.”

Catherine, Duchess of Cambridge sits on a log with children during a visit to Sayers Croft Forest School and Wildlife Garden on Oct. 2, 2018 in London. Sayers Croft is an activity center aimed at educating and involving children and the local community in the environment.

Catherine, Duchess of Cambridge sits on a log with children during a visit to Sayers Croft Forest School and Wildlife Garden on Oct. 2, 2018 in London. Sayers Croft is an activity center aimed at educating and involving children and the local community in the environment. (Getty )

Visiting the Paddington Recreation Ground area school, which immerses city children in nature, the mother of three revealed that she likes going on “spider hunts” with Prince George, age 5, and Princess Charlotte, age 3, in their own garden at home, The Telegraph reports.

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As noted by New York Daily News, Duchess Kate has been known to “recycle” her dozens of high-end outfits, most recently stepping out in a favorite cornflower blue Catherine Walker coat for her friend Sophie Carter’s wedding on Sept. 24. All bets are on that she’ll do the same for the royal wedding of Princess Eugenie and Jack Brooksbank on Oct. 12.