We continue west to see on our left-hand side the barracks of the ‘Vigili’ (fire brigade). This two-story space was also used by the staff.
A bit further ahead we find the court of the Dorian columns. The building was a basilisk where Hadrianus judged. The rectangular hall measured 32 x 32 metres. The building was surrounded in part by a portico, supported by 36 pillars. The capitals and the base of the pillars were made in the Dorian style. A part of these pillars with the architrave, frieze and with the closing barrel vault can still be seen today.
The Dorian columns are special in that they deviate completely from classical canon. The renewal of the columns is much stronger than allowed by classical (vitruvian) rules.
We subsequently arrive at the quadriportico with a fish pond and a cryptoporticus, which we will of course enter. If you look closely, you can make out quite a bit of graffiti, including a signature by the famous Giovanni Battista Piranese.
We head towards the most western excavated building: the Piazza d’Oro. Architecture-wise, this is one of the most striking and interesting buildings. If you attend the daily programme VI, which covers the 17th century architect Borromini, you should pay attention to how many elements of the hypaethral find their way with Borromini.
The building consists of a large square gathering of columns of 100 x 60 metres, with a pond at the very centre, which in turn is surrounded by a garden.
The map of the Piazza d’Oro:
1.Entrance with an octagonal ribbed vault 2. Double colonnade of the peristilium 3. Axial pond 4. Courtyard 5. Hypaethral room with complex curved lines 6. Nympheum shaped like an exedra
Interestingly, the hypaethral room with the nympheum behind it is shaped like a quarter circle. The hypaethral (Greek: hypaithrs = below the open sky) is a centred plane with an octagon within which a cross-shaped map is written. The walls of this cross shape alternate between concave and convex. In addition, it uses central and diagonal axes. Maps with these types of axes have greatly influenced baroque architecture. Baroque artists, including the likes of Cortona, Borromini and Bernini often used central maps with concave and convex wall spaces.
The entrance building across from the hypaethral room is also remarkable. This too boasts a central map with curved walls. The dome is supported with an octagon ribbed vault. The striking thing is that only eight pillars support this vault, and similar to the Pantheon, eight pillars support the domes.