I have only minimal information at the moment, but I believe I will be the sole Doctor representing Loudoun in attendance. I have never been as far north as New York, and know very little about Fort Niagara itself.
From the Niagara site, about the event:
2009 marks the 250th anniversary of the historic siege of Niagara, and Old Fort Niagara plans a large-scale commemoration of the event. On July 3-5 Old Fort Niagara will host a gigantic Living History encampment that will re-create the siege with over 2300 re-enactors portraying British and French forces and Native American warriors. This event has been named as the signature event for 2009 by the New York State French & Indian War 250th Anniversary Commemoration Commission. The French and Indian War Grand Encampment Council has also named the event as the Grand Encampment for 2009 making this the largest event of its kind in the world for 2009. Plans for the three-day event call for extensive battle re-enactments, a nighttime artillery bombardment with fireworks, naval forces, and large living history camps filled with people portraying 18th century soldiers and artisans.
For more information about this event and a tentative schedule for the weekend, Visit the Niagara site.