  Archeological Roman lead (Pb) is known to be a suitable material for
shielding experimental apparata in rare event searches. In the past years the
intrinsic radiopurity of this material was investigated using different
technologies. In this work we applied the latest advancements in cryogenic
techniques to study the bulk radiopurity of a 1 cm$^{3}$ sample of
archeological Roman Pb. We report the lowest ever measured limit on $^{210}$Pb
content in Roman Pb, with a concentration lower than 715 $\mu$Bq/kg.
Furthermore, we also studied $^{238}$U and $^{232}$Th impurity concentrations.
Our values concur with independent measurements reported in literature.
