The finely made base is decorated with a relief of interwoven plane-tree branches surmounted by bucrania (ox skulls). The rectangular setting on the base's upper surface suggests that it was used as a plinth for a statue, perhaps of Hercules. In the area of its discovery, there was probably an open-air sanctuary dedicated to the hero, for whome the plane tree was sacred.
There are visible suggestions of degraded pigments, but I couldn't find whether any tests had been performed on this base (I doubt it).
Roman, from Rome, lungo il Tevere (banks of the Tiber River) in front of the Castel Sant'Angelo. Augustan period, late 1st century BCE-early 1st century CE)
Museo Archeologico Romano, Palazzo Massimo alle Terme, Rome (inv. 417)