The weekend-long affair saw Kathryn, her husband Padraig and daughter Ellie dance the night away in the spectacular castle grounds.
Thomas caught up with fellow presenter Ray D’Arcy at the 2019 National Ploughing Championships to discuss all things wedding-planning and how she managed to create the perfect dress.
"My thing was, I wanted a kind of a festival," she tells RTÉ.
"The music started just before the desserts came out and I hit the dance floor and I didn’t stop 'til Monday."
Speaking about the gown, Kathryn revealed that her dress was custom made by Irish-based designer Umit Kutluk.
Thomas said that, above everything else, she knew she wanted a statement back
"Anytime I’m at a wedding, I love looking at the back of a bride’s dress. I’d seen this photograph, maybe four or five years ago, of a couture Chanel dress and it had that big sort of oversized bow," she told Ray.
"I brought him the photograph and he said, you know I don’t think we can make that. It took a long time to get it right, but we got it. I loved it. I felt really comfortable and I felt really confident on the day."
The custom made dress turned heads with its deep V at the back, created by folds of ivory silk meeting just below the small of her back in an oversized bow.
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