Kate arrived at Cadogan Pier this afternoon and readied herself for the journey down the Thames. There were about a thousand other boats that followed behind the Flotilla to celebrate the Queen.
The frock has also been worn by Kim Kardashian and Tulisa who were photographed wearing a short-sleeved version of it last year. Kate's version had full length sleeves and a longer hemline than the original.
Photo credit: The Royal Wedding Dress on FB
The Duchess of Cambridge matched her dress with a vivid red Sylvia Fletcher hat from James Lock & Co (£795) while her hair was safely held in place in a half up do.
She accessorized with her nude LK Bennett 'Sledge' heels (£185) and a small red clutch also by Alexander McQueen. It looked very much like the Alexander McQueen Classic Skull Clutch in Red Velvet sans the skull. Perhaps it was a bespoke version.
Kate also carried a Strathearn tartan scarf. This is believed to be a a nod to her Scottish title the Countess of Strathearn, a title she uses in Scotland.
Photo credit: My Small Obsessions on FB
Finishing off her look, Kate doned a maritime-themed brooch featuring two dolphins - a gift from the Royal Navy Submarine Service, of which William is Commodore in Chief. She also wore her Kiki McDonough Citrine Drop Earrings.
Kate came prepared for the rain with a custom red umbrella by the Royal warranted umbrella maker, Fulton. The Duchess' umbrella was custom made to match her McQueen dress. It's the men's Huntsman's style and retails for £19.