The Palatine complex, constructed by Octavian between 36 and 28 B.C., included the Temple of Apollo, the Portico of the Danaids, Greek and Latin libraries, and Octavian's own residence. Although excavations of the past 50 years have revealed much of this monumental complex, the design and location of the Portico of the Danaids remain debated. This article draws on field research, previously published archaeological reports, literary evidence, and architectural comparanda to argue that the portico stood on the terrace of the Temple of Apollo and to reconstruct the elevation as a two-story Doric colonnade in which the statues of the Danaids alternated with the columns of the second story. In addition to shedding new light on both the location and appearance of the portico, this article reveals how the cross-fertilization of the orders and arithmetic relationships throughout the elevation generated a coherent aesthetic whole. In so doing, this study offers new insights into the so-called architectural revolution of the triumviral period and highlights the significance of the Palatine complex within this shift.