All of know of for certain thus far are:
Bull Run March 26 2011
Casanova March ? 2011
Farmington Hunt March 5, 2011
Rappahannock October 30, 2010
Od Dominion October 30, 2010 (held with Rappy’s)
Middleburg February ? 2011
Caroline October 16, 2010 (per above)
Deep Run March ? 2011
Keswick March or April ? 2011
Blue Ridge November ? 2010
Fairfax March ? 2011
Neither Orange nor Piedmont have one. I think Warrenton’s is usually in the winter. Snickersville and Thornton Hill have an event but not exactly a ball (I think). Reedy Creek, Oak Ridge, Glenmore, Rockbridge, Middlebrook, Princess Anne, all have bona fide balls; ck their websites or www.foxhunt.va. Not sure about Colonial, Bedford, Stonewall, Loudoun or Loudoun West; I don’t think Commonwealth has one anymore.
Hands down, Casanova ALWAYS has the best show.