<p>Huge circular tomb, some 40 m in diameter, situated prominently on the *Aventine’s extramural SE lobe in the former Vigna Cavalieri, perhaps not far from a regional road (s.v. *Via Ardeatina; Scagnetti G9; Lanciani, <i>FUR</i> pl. 45; for its plan and construction: Eisner). The exterior of the cylinder, whose core of <i>opus caementicium</i> still stands 5.5 m high, was revetted with travertine blocks (of which some fragmented headers are still preserved). A barrel-vaulted radial tunnel, built mainly in <i>opus reticulatum</i>, still provides access to the center tomb where a vaulted ring chamber with 5 niches is constructed around a central pillar; its function may have been to support a <i>cippus</i> or statue on top of the tumulus’ mound (Gros). Because of its type and grand size, along with the use of <i>opus reticulatum</i>, the tomb has been attributed to the last years of Republic or first decades of the Principate (Gros; cf. Eisner 210). No clue exists as to its ancient owner.</p>