Helo meets Sharon here in episode #113 "Kobol's Last Gleaming: Part 2" and shoots her on the stairs.
Filmed at SFU's Academic Quadrangle and Convocation Mall. The location of a conversation between Baltar and Number Six in the miniseries. Also Roslin's flashbacks from episode #213 "Epiphanies".
Source: BSG Season 1 Location Guide