Prince Charles and Prince Harry look so alike with a beard - see the incredible photos

The Duke of Sussex has long sported facial hair and first debuted a full beard on Christmas Day in Sandringham back in 2013.

But he's not the only royal to have experimented with his look over the years.

Prince Harry's father, the Prince of Wales, surprised attendees at the Badminton Horse Trials in 1976, when he wore a full beard in public.

READ: Meghan Markle's sweet reference to Prince Harry in new book almost went unnoticed

WATCH: Royal men with beards through the years

And royal fans were quick to comment on how much Harry and Charles resemble one another when the photo of the Prince of Wales resurfaced on social media this week, with one saying: "Like father, like son."

It was thought in the lead-up to his wedding to Meghan Markle in May 2018 that Harry would opt to be clean-shaven, given that he was wearing military uniform.

Prince Charles pictured with a beard in 1976

While military regulations have previously stated that members of the armed forces should be clean shaven, the British Army's policy on facial hair has been reviewed in recent years.

MORE: Beard or no beard? 9 times these royal men sported very different looks

MORE: Duchess of Cornwall reveals personal family photos with glimpse inside royal home

Harry kept his beard on his wedding day

According to Forces.net, regulations for the British Army state: "Beards and whiskers are only to be worn with authority, which will usually be granted only on medical or religious grounds, or where tradition permits.

"The appearance of the beard and whiskers is to be neat and tidy. Sideburns are not to descend below the mid-point of the ear and are to be trimmed horizontally."

William debuted a beard in 2008

Harry's older brother, the Duke of Cambridge, has also experimented with his facial hair in the past.

Prince William surprised royal fans when he attended church on Christmas Day in 2008 sporting a beard. But it was short-lived, and the Duke has remained clean-shaven ever since.

Make sure you never miss a ROYAL story! Sign up to our newsletter to get all of our celebrity, royal and lifestyle news delivered directly to your inbox.

ncG1vNJzZmivp6x7qbHLpaammZeWx6q6xGeaqKVfp7y6rcutsGhqYGd%2BcYGPbmhqamRqgHC80aKlnJ1dmLWivsueqmaoop67pLGMoZirqqliubC7ymaqqGWRobassYywoK2gXZeyor7DrGY%3D