I was feet away from Prince Harry and Meghan Markle at their first joint royal event in 2 years. Here's what it was like behind-the-scenes.

• I was at Prince Harry and Meghan Markle's first public UK event in years.
• Hundreds of people and members of the press showed up to see the royals.

The Duke and Duchess of Sussex made their first joint public appearance in the UK after two years, and I was there to witness the behind-the-scenes mania.

The couple attended the Service of Thanksgiving at St. Paul's Cathedral in London for the Jubilee weekend on Friday in honor of the Queen's 70-year anniversary on the British throne. While Her Majesty was unable to attend the event, senior royals and British politicians showed up to pay tribute.

St. Paul's is a cathedral and visitor attraction that is most famously known for being the location of Princess Diana and Prince Charles' wedding in 1981. I have visited a handful of times, but the crowds I witnessed there on Friday were unlike anything I'd ever seen there.

I arrived around an hour and thirty minutes before the service was due to begin, and hundreds of people were already gathered outside the cathedral. The entrance had been cordoned off, and royal fans stood at the barriers waving Union Jack flags and snapping photos.

As the attendees started to arrive, it became increasingly difficult to see over the stream of people who snapped their phones and cameras in the air. There were even members of the press conducting interviews in the middle of the crowd.

It was so crowded, in fact, that when UK Prime Minister Boris Johnson arrived, I could only tell it was him by the public's reaction. Loud boos erupted all around before the people standing in front of me confirmed that Johnson had made his entrance.

When Harry and Meghan arrived, I had a slightly better vantage point, and I managed to get a video.

Just like the other royals who attended the event, Harry and Meghan were met by loud cheers. (Although, I later learned that the couple was booed when they left, which I didn't witness myself.)

Although the service was private, photos were released to the public. I was curious to see if there would be images of Harry and Meghan reuniting with Prince William and Kate Middleton. Harry and William have been rumored to be in a rift for years, and they previously appeared to avoid speaking with one another at the Sussexes' final royal engagement before their step back in 2020.

At Friday's event, there was no interaction between the two couples as they were seated in different rows. Kate and William sat in the first row with Charles and Camilla, while the Sussexes were in the second row.

According to the royal historian Marlene Koenig, the seating arrangements could have been intentional.

"In a normal [circumstance], they would have sat next to them by precedent," Koenig told me of the Sussexes' and Cambridges' seating positions.

"I absolutely think, first and foremost this event isn't about William and Harry, it's about the Queen ... But I do think — I don't know — but I think there was a concerted effort to make sure, you didn't want them sitting next to each other both stoic, with people making all sorts of comments and speculation," she added.

Koenig added that it made perfect sense for the Cambridges, Charles and Camilla to sit in the front row, "especially Charles as he is representing the Queen."

Buckingham Palace and Kensington Palace did not immediately respond to Insider's request for comment.