18 July 2011 Last updated at 10:58

The Beatles in the USA

The Fab Four made two hysteria-inducing visits to America in 1964, launching the so-called "British Invasion" of the mid-1960s.

As they visited Washington DC and Baltimore a young photographer, Mike Mitchell, snapped dozens of images of John, Paul, George and Ringo.

Now, after being filed away for nearly 50 years, these never seen before black-and-white photographs are being sold at auction at Christie's in New York.

Take a look at some of them, and hear The Beatles perform and talk about their visits to the USA.

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The Beatles Illuminated: The Discovered Works of Mike Mitchell will be auctioned at Christie's New York on 20 July.

All images copyright Mike Mitchell and courtesy Christie's. Music by The Beatles. Additional audio from BBC Archives.

Slideshow production by Paul Kerley. Publication date 18 July 2011.

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