In order to refine my previous reply about said topic, here goes:
Wolf Trap is in the Reston, VA area near Washington. Get on the Capital
Beltway and look for signs. (BTW- from Richmond, take 95N to the beltway
and head WEST). From Md, take the beltway and head west or south until
you get to Reston, "I suppose".
Dana McCall
Chapel Hill