The gown is a design by Sarah Burton for Alexander McQueen's fashion house.
"Miss Middleton chose British brand Alexander McQueen for the beauty of its craftsmanship and its respect for traditional workmanship and the technical construction of clothing," the palace said in a statement. " Miss Middleton wished for her dress to combine tradition and modernity with the artistic vision that characterizes Alexander McQueen's work. Miss Middleton worked closely with Sarah Burton in formulating the design of her dress."
The dress is made from ivory and white satin gazar, and the bodice and skirt feature hand-cut English lace and French Chantilly lace. The train measures almost nine feet long.