Kate Middleton is remembering Britain’s longest-reigning monarch.

On Wednesday, the Princess of Wales accompanied her husband Prince William to King Charles’ coronation celebration in Scotland. The 41-year-old attended the National Service of Thanksgiving and Dedication at St. Giles’ Cathedral in Edinburgh. According to the Scottish government, the church service was organized in honor of the king and Queen Camilla's coronation in London.

Charles, 74, and his wife were crowned on May 6 at Westminster Abbey.

For the outing, the mother of three wore Queen Elizabeth II’s four-row Japanese pearl choker with a diamond clasp, People magazine reported. The jewels were paired with a pearl bracelet and earrings that once belonged to Middleton's late mother-in-law, Princess Diana.

CATHERINE, PRINCESS OF WALES MAKES SMALL ERROR PLAYING TENNIS WITH ROGER FEDERER ON WIMBLEDON COURT: WATCH

A close-up of Kate Middleton in blue wearing a pearl choker

Catherine, Princess of Wales, outside St Giles' Cathedral, for the National Service of Dedication on July 5, 2023, in Edinburgh, Scotland. (Phil Noble - WPA Pool/Getty Images)

According to the outlet, the princess wore the choker at the queen’s funeral in September 2022, Prince Philip’s funeral in April 2021, as well as the couple’s 70th anniversary party in 2017.

The queen passed away on Sept. 8 at Balmoral Castle. She was 96.

British royals expert Shannon Felton Spence told Fox News Digital that Scotland holds special significance for the royal family. Still, it didn’t stop protesters from chanting "Not my king" upon Charles’ arrival. According to Sky News, two women were arrested as the king received Scotland's crown jewels at the cathedral.

A close-up of Kate Middleton smiling wearing a blue dress and a pearl choker necklace

For the service, Kate Middleton wore her late grandmother-in-law's pearl choker. (Samir Hussein/WireImage)

"The queen died in Scotland," Felton Spence explained. "The king’s grandmother was Scottish, so it is a very special place to them. But traditionally there is a lot of historic trauma between the Scottish people and the crown, which is why there is more protest at this coronation that the one at Westminster Abbey."

"… Scotland is a separate realm," she shared. "The coronation in London wasn’t for the U.K., it was for the Church of England. The Church of Scotland is separate."

In her lifetime, the queen had a great love for Scotland. Balmoral Castle was a place of refuge where she could relax with her family, the BBC reported. As a child, she spent a lot of time in Scotland, either with her parents or maternal grandparents. As a teen, she also gave her first public speech in Aberdeen. And as queen, she looked forward to her annual family holiday at Balmoral.

QUEEN ELIZABETH DENIED HER UNCLE'S DYING WISH FOR THIS REASON, DOCUSERIES REVEALS

Queen Elizabeth wearing a hot pink coat with Scottish guards surrounding her

Queen Elizabeth II at the gates of Balmoral on Aug. 9, 2021. The queen passed away in September 2022. She was 96. (Jane Barlow - WPA Pool/Getty Images)

"I have spoken before of my deep and abiding affection for this wonderful country and of the many happy memories Prince Philip and I always held of our time here," she said in 2021 at the opening ceremony of the Scottish Parliament. "It is often said that it is the people that make a place, and there are few places where this is truer than it is in Scotland, as we have seen in recent times."

Middleton completed her look with a royal blue coat dress featuring a velvet collar by Catherine Walker & Co. The ensemble was previously worn for Easter, as well as the Commonwealth Day service in 2022. She also opted for a matching Philip Treacy hat.

The princess rode in the Royal Procession with William, 41. The prince wore his Royal Air Force No. 1 uniform, as well as his Garter Sash with the Lesser George, RAF Wings and Golden Jubilee, Diamond Jubilee, Platinum Jubilee and coronation medals, People magazine reported. According to the outlet, he also sported his Most Ancient and Most Noble Order of the Thistle Mantle and Collar, which reflects his position in Scotland’s highest order of chivalry.

Kate Middleton in a blue dress sitting next to Prince William, King Charles and Queen Camilla

Catherine, Princess of Wales, Prince William, King Charles III and Queen Camilla attend the National Service of Thanksgiving service at St Giles' Cathedral on July 5, 2023, in Edinburgh. (Andrew Milligan - Pool/Getty Images)

In Scotland, the Prince and Princess of Wales are known as the Duke and Duchess of Rothesay.

The outlet noted that the couple traveled in the royal Rolls-Royce, following the king and queen in the state Bentley.

"This is not the big show," said Felton Spence. "We already had that at Westminster Abbey. It's important for the Prince and Princess of Wales to be there… But it’s a much smaller occasion. Remember, Scotland is very important and special to William and Catherine as well – they met at St Andrews."

KATE MIDDLETON HONORS PRINCESS DIANA AT KING CHARLES’ TROOPING THE COLOUR

Kate Middleton wearing a blue dress leaving a car

Kate Middleton met her husband Prince William as a student at the University of St. Andrews in Scotland. (LESLEY MARTIN/POOL/AFP via Getty Images)

"The royals love Scotland," she continued. "But not all of Scotland loves them. For hundreds of years, it’s been a very uneasy relationship. Scotland voted to remain in the U.K. in 2014 but then voted to remain in the EU in 2016. The ruling Scottish Party – the SNP – campaigns for a Free Scotland. So, this coronation has a lot of interesting dynamics that affect modern-day politics."

"Scotland holds many memories for the royal family," Ian Pelham Turner chimed to Fox News Digital. "Charles normally wears a kilt on any normal public appearances. For William, it is where he first heard about his mother's death... William and Kate value their Scottish title. In the summer holiday period, they make many unannounced but welcomed public appearances."

"Queen Elizabeth II's coffin lay in state in St Giles' before being moved to England," royal expert Richard Fitzwilliams told Fox News Digital. "King Charles has a deep love of Scotland. His Trust is highly respected, and his charitable projects are impressive."

a close-up of Kate Middleton wearing a black dress at a funeral

Kate Middleton previously wore Queen Elizabeth's pearl necklace during the late monarch's funeral. (Samir Hussein/WireImage)

CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER

"It will be one of the main challenges of his reign to keep the United Kingdom together," he shared. "Today’s impressive ceremonial will certainly have helped."

The Prince and Princess of Wales’ three children were not in attendance. Prince George, 9, Princess Charlotte, 8, and Prince Louis, 5, are completing their last week of classes before summer break, People reported.