NICE FIRST POST!
"Signature" runs in the mid-Atlantic are pretty modest, but here are a few nominations.
Whitetail, PA: DBos mentioned Exhibition at Whitetail and I would agree with that, unless they switch things up and make Bold Decision their bump run like they used to.
Liberty Mtn, PA: used to be White Lightning until they built the backside trails. Now with those it's a tougher call, but I'd say Upper and Lower Eastwind.
Roundtop, PA: it's gotta be Gunbarrel.
Seven Springs, PA: a few runs come to mind, but I'd say Wagner Trail since it runs through the heart of the ski area.
Wisp, MD: perhaps The Face.
Timberline, WV: White Lightning
Canaan Valley, WV: Valley Vista
Snowshoe, WV: tough call, either Cupp Run or Shay's Revenge
Massanutten, VA: a few runs come to mind, maybe Diamond Jim.
Wintergreen, VA: Cliffhanger
Blue Knob, PA: Extrovert. In my mind the standout run in the mid-Atlantic. It's pretty steep for our region and often icy and bumpy with some dirt and rock showing through. The steep part is more or less continuous for about 600 vertical feet:
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