Bobby Carter over at the Diversion LAB breaks this one down for you:

“York Jam was the mecca of flatland jams. It was like, if you were in the flatland game for a certain amount of time, at least once in your life you had to make the journey to York to participate in this event. 2002 was my year.
Riders include: Matt Wilhelm, James Kennedy, Brian Chapman, Stephen Cerra, Marcos Paulo de Jesus, and many more!”