This is one of several drawings of the Roman aqueducts that Robert Adam made, perhaps at the suggestion of Piranesi, although there is another possible source in a pencil drawing by Jean-Baptiste Lallemand (see Adam vol.57/7). The curving structure in the distance may be the branch of the Arcus Neroniani. Adam vol.57/89 may depict the same subject taken from a different position, with the villa pavilion in the distance. Adam made a drawing of the antiquities in a villa garden, probably that of the Villa Celimontana, in Adam vol.57/50.
The Acqua Claudia, of the 1st century AD, had the Arcus Caelimontani as its western branch.