He financed the restoration of the damages made by an earthquake[which?] to the Colosseum of Rome; two inscriptions are still extant, reading (CILVI, 1716 b and c):
DECIVS MARIVS VENANTIVS BASILIVS V[IR] C[LARISSIMVS] ET INL[VSTRIS] PRAEF[ECTVS] VRB[I] PATRICIVS CONSVL ORDINARIVS ARENAM ET PODIVM QVAE ABOMI NANDI TERRAEMO TVS RVINA PROS TRAVIT SVM[P]TV PRO PRIO RESTITVIT
Decius Marius Venantius Basilius, vir clarissimus and inlustris, Praefectus urbi, Patricius, Consul ordinarius restored at his own expenses the arena and the podium, destroyed by a terrible earthquake