Kate Middleton Just Shared a New Family Photo and Royal Fans Love Her Off-Duty Look

Rare Photo Shows Kate in a Baseball CapMark Cuthbert - Getty Images

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Kate Middleton may be best known for her fabulous coats, tailored suits, and enviable jewelry collection, so it's always a treat to catch her in something a little more casual. And that's exactly what we got when she recently shared a family photo honoring Mountain Rescue Awareness Day.The sweet snapshot shows the royal couple alongside their three children, Prince George, Princess Charlotte, and Prince Louis, alongside mountain rescue volunteers. The photo was taken during the National Three Peaks Challenge this past summer, during which Kate tackled the three highest mountains in the United Kingdom.

Though much of Kate's outfit is obscured in the family portrait, previously released photos from the hike give us a much better look at her sporty ensemble. The Princess of Wales was bundled up in a brown Härkila Sandhem Pro Insulated Cardigan, a quilted fitted jacket with cozy fleece sleeves. Per the brand, it blocks the wind and provides lightweight warmth, making it a practical choice for a day in the mountains. She paired it with a navy top and bright red Summit Series Pacesetter 3″ Shorts from The North Face, adding a cheerful pop of color.

As for shoes, Kate chose a pair of brown Scarpa hiking boots with waterproof leather and sturdy, grippy soles. If they look familiar, it's because we've covered her trusty hiking boots before. She also carried a dark olive Fjällräven daypack, rounding out her outdoorsy ensemble.

But the real standout? Kate in a baseball cap. She wore a classic navy style, with her ponytail pulled through the back opening. After a little digging, I found her exact cap: Fjällräven's Est. 1960 Cap in Dark Navy, which retails for $45. Unfortunately, the color she wore is currently out of stock. The good news? Plenty of similar options are available to shop.

This isn't the first time Kate has made a case for the accessory. From sailing trips to beach days, baseball caps have been a recurring favorite in Kate's closet. Just earlier this year, she paired a baseball cap with a houndstooth blazer and suede cowboy boots, proving sporty and polished pieces go hand in hand.