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Guests at Prince William's 21st birthday party at Windsor Castle adopted the African dress code with gusto.

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Safari outfits were a common option, along with foreign legion and colonial uniforms.

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William thought up the idea - inspired by visits to Africa - and was in sole charge of the guest list.

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Even the Windsor crowds outside made an effort to enter into the party spirit.

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One of the most inventive costumes was a banana, but that was run close by a witch doctor and a furry lion with a crown.

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Some of the prince's university friends arrived by minibus, which was decked out in a birthday greeting.

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Crowds lined the Windsor streets to greet and cheer arriving party guests.

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But the Queen kept everyone guessing about her costume, as she arrived from Ascot.