Firehouse Pillar forms a wide sustained steep curtain of ice ~70 feet high. The climb is wide enough to accommodate several parties, with varied terrain across the width of the curtain. Because of the many route variations, I believe a range of grades is more accurate than the WI4 rating listed in the Roberts book. The left hand side forms into a vertical chandelled pillar. The middle forms a smoother, less steep ~80 degree curtain. The right side is a low angle bulgy slab that provides the easiest access to the top for the moderate leader. Descent: Rappel slings and rap rings from trees at the top.
Addendum: note the exact location of this pillar can vary annually.