Many years ago, on visiting a retrospective show of Ludwig Mies van der Rohe's drawings and full-size models in the Museum of Modern Art, New York, this author was astonished at how formative was the tectonic of column/wall for the German architect's work. In this chapter, the author demonstrates the singularity of Mies's work as far as it concerns a modernist return to the tectonic of the column and wall. To this end, the author intends to centre Mies in the historical debate between Alois Riegl and Gottfried Semper. The intention of this brief reiteration of the near past history of architecture is to cast some light on the tectonics involved in architecture's transformation from the haptic to the optic realm – to recall Riegl's formulation of the formal development of art and architecture. Besides the historian's theorization of architectural history, equally important is an architect's rapport with architecture's past.