<p><i>Opus incertum</i> walls belonging to several houses of the 2nd c. B.C. have been found inside the Servian Wall (*Muri: Aventinus) on the brow of the *Aventine overlooking the Tiber (just NW of S. Sabina). Nearby, reticulate walls, of late-Republican or early-Imperial date, reach into the area just outside the wall (Lanciani, <i>FUR</i> pl. 34); to facilitate circulation, four passageways were opened in the wall, and thus the wall’s defensive function had clearly been abandoned (Coarelli). While the remains are too insubstantial to yield a ground-plan, the location of the finds is marked on our map.</p>