The excavation covered a triangular area of circa 976m2 , which intercepts part of the area situated between via Alessandrina, via Bonella, via del Priorato and via dei Carbonari. The block was built at the end of the 14th century and demolished in 1931-32 to make way for the creation of via dei Fori Imperiali. Removal of the rubble revealed the presence of four adjacent housing blocks (named 1, 2, 3 and 4 starting from the south-eastern block). Of these four blocks the north-eastern limit, facing onto via Alessandrina, is preserved, whilst the limit of block 1 facing onto via Bonella is preserved for a length of 12m. The south-western side of the blocks continues outside the edge of the excavation and continues below via dei Fori Imperiali. Of the central and eastern parts of the complex the cellars, with collapsed vaults are preserved, it is only in the western part that the ground floor service rooms and parts of the courtyards are preserved. The interpretation of the stratigraphy relating to the standing remains led to the identification of five occupation periods for this sector of the quarter taken into consideration.

At the end of the 16th century (Period I: 1580-1600) the Della Valle and Ghislieri families took it upon themselves to promote the urbanisation of the Palatine’s northern zone. Firstly, Palazzo Ghislieri (block 1) was built, whilst Palazzo Longhi and other adjoining residential structures towards the west (blocks 2-4) abutted the north-western perimeter wall of this palazzo.

In the next two centuries (Period II: 17th-18th century) modifications were made inside the two blocks. The courtyard of Palazzo Ghislieri was partially encroached upon by discontinuous foundations, with alterations to the roofing of the cellars.

In the first half of the 19th century (Period III) a storey was added and restructuring undertaken, traces of which remain in the cellars (the round arches in block 1 were reinforced and a pilaster was inserted in block 2 indicating problems of instability). Following the heightening of the buildings the spaces were also reorganised.

In the second half of the 19th century (Period IV) the successive restructuring involved the ground floors preserved in the western parts of the buildings.

The 20th century (Period V) interventions involving the ground floors (and to a lesser degree the cellars) are recognisable by the use of cement mortar and did not alter the structural layout of the buildings, but were only modifications of a secondary nature undertaken in individual rooms.

In the years 1931-1932 the buildings were demolished as part of the project which created the via dei Fori Imperiali. The walls were razed and the area was levelled with an accumulation of building debris from the demolition itself. (MiBAC)