In the condensed styles of most geometric slab serifs, weak ovals replace the powerful circular forms. In Citadel, Tobias Frere-Jones follows a stronger alternative, substituting straight strokes for the curved sides of round characters. Flat horizontal curves play against the variety of serifs, in counterpoint to the repeating rhythm of verticals. In the Inline style, the stripe adds to that rhythm, creating a typeface that offers a powerful and stylish geometry.