Meghan Markle and Prince Harry Have a Keepsake From Their Secret 'Backyard Wedding' in Their Room

Meghan Markle and Prince Harry wanted to celebrate their union in a more intimate way before they exchanged formal vows before an audience of millions.

Just days before their royal wedding at St. George's Chapel at Windsor Castle on May 19, 2018, the couple planned an impromptu backyard ceremony just for the two of them.

"Three days before our wedding, we got married — no one knows that — but we called the Archbishop and said, 'This thing, this spectacle is for the world, but we want our union between us,' " Meghan told Oprah Winfrey during her interview on March 7.

RELATED: Your Burning Questions from Meghan Markle and Prince Harry's Oprah Interview — Answered

To remember the special ceremony, the Duke and Duchess of Sussex had a special keepsake made that they now have displayed in their room at their Montecito home in California.

Meghan Markle and Prince Harry

"So the vows that we have framed in our room are just the two of us in our backyard with the Archbishop of Canterbury," Meghan added.

Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more!

Ben STANSALL - WPA Pool/Getty Images Prince Harry and Meghan Markle on their wedding day

Days later, Meghan and Harry stepped onto the world stage to officially become husband and wife. And despite the fanfare around their royal wedding, Meghan approached the big day with a sense of calm.

"I've thought about this a lot because it was like having an out-of-body experience I was very present for," she told Oprah. "That's the only way I can describe it because the night before I slept through the night entirely, which in and of itself is a bit of a miracle."

Get the premiere issue of PEOPLE Royals for glamorous new photos and inside stories royals fans haven't seen or read elsewhere! Subscribe at peopleroyals.com/launch

"And then woke up and started listening to that song 'Going to the Chapel.' And I just tried to make it fun and light and remind ourselves that this was our day — but I think we were both really aware, even in advance of that just, this wasn't our day. This was the day that was planned for the world," she added.