Between July 2011 and November 2012, archaeological investigations were undertaken inside the building standing at piazza Dante 25, a former post-office. The work was carried out as part of a project to modernise the 19th century building, which occupies the southern side of the piazza. To date the investigations have involved the interior courtyard and, partially, the south wing of the building and the southern external pathway. The stratigraphy covered a sequence running from the Republican to modern period, and was heavily compromised by the redevelopment of the Esquiline quarter at the beginning of the 20th century, which saw the complete razing of the summit of this slope and consequently of most of the archaeological evidence present in the northern part of the area under investigation. Despite this, five occupation phases were identified. The earliest phase was attested by the pozzolana quarries, which appear to have been active for a long period. Quarrying was mainly open-face; in fact, only one sector of the quarry was partly in a tunnel. Unfortunately, it is impossible to define an absolute chronology for these quarries that seem to have been active between the 1st century B.C. and the 1st century A.D. at least. In a period immediately after the abandonment of the quarries, the small, natural valley was levelled and this was followed by large-scale topographical and urban reorganisation. The valley, like the part of the quarries that was still visible, was covered by massive fills, which raised and evened out the new ground level. In order to avoid land slippage into the channel, two walls were keyed onto its edges using reused _cubilia_ ;these walls served to break the slope and contain for the fills. From this time onwards, the appearance and function of this part of the Esquiline area changed forever. Very deep cement foundations were laid within the fills, following and extending the contours of the hill, thus creating an imposing system of substructures. These structures can partially be identified as the foundations of the _Horti Lamiani_, as indicated by Lanciani in the _Forma Urbis_ (figs. 30-31): unfortunately, all that remains of this building phase, datable to the second half of the 1st century A.D., are faint traces of supporting walls. No evidence of the floor surfaces survives, mainly due to the 19th century razing. The two subsequent phases refer to the modern and contemporary eras and are attested by a small building, perhaps relating to the Villa Palombara, and of course to the great palazzo of the Casse di Risparmio Postali, dating from the time of king Umberto I. The investigations are continuing and it is hoped that the new data will make it possible to produce a clearer picture of the topography, structure and chronology of this important, if limited, archaeological evidence for this part of the Esquiline quarter.