The Great Gathering (York) 3-17 July 2013.

Mallard and its five surviving sister A4 locomotives will mark the calendar anniversary of Mallard's record-breaking run by gathering together around the Great Hall turntable at York.
That's the three operational A4s - Sir Nigel Greeley, Union of South Africa and Bittern - plus Dwight D Eisenhower, Dominion of Canada and Mallard.

  I will be going 

Me too 

What date?

Not sure yet as I am taking my father in law and it depends when he can make it.  Probably mid-week though to avoid the weekend crowds.

Same with me midweek taking me, myself and I going by train can't be bothered to drive.