Circo Apollinare d'Adriani. «Dalle vestigie scoperte pochi anni fa nel sito ove l'abbiamo delineato.» mentre il Rosati, e Canuti pastinavano questa parte di fondo del subborgo.
Circus Hadriani as delineated within the first state of the Ichnographia Campus Martius.
Vincenzo Fasolo, "The Campo Marzio of G. B. Piranesi".
book on the Campo Marzio
...the actual existence of a Circus Hadriani as per the Nolli plan...
excerpts from Procopius
one more Piranesian daze: circus act
In attempting to discern the possible reason or message manifested by the plan changes to the Circus of Caligula and Nero and to the Circus Agonalia, I began to think of these specific circuses and how they may or may not relate to the numerous other circuses delineated throughout the Ichnographia. Within the version of the Ichnographia that is presently widely published there are six circuses, the Circus Caji et Neronis, the Circus Agonalia, the Circus Hadriani, the Circus Domtiae, the Circus Flaminius, and the Circus Apollinaris. With only minor adjustments to length, each circus is delineated in a virtually identical fashion, and, moreover, each circus reflects an archaeologically correct circus plan. As already illustrated, the plans of the Circus Caji et Neronis and the Circus Agonalia within the University of Pennsylvania Ichnographia reflect more stylized, i.e., archaeologically incorrect, circus formations. Since all the circuses are identical in the widely published version of the Ichnographia, I then began to wonder, via transposition, whether all the circuses within the Penn Ichnographia were likewise identical there in the form of exhibiting plan changes. In all honestly, I had not noticed any plan changes to the circuses other than the Circus Caji et Neronis and the Circus Agonalia the two times I had seen the Penn Ichnographia prior, but nor did I have any pictorial hardcopy evidence that there are no other plan changes. Having worked with the Ichnographia for over ten years, if I have learned anything, it is that the Ichnographia, no matter how well you think you know it, continually maintains the uncanny ability to beguile. Therefore, it was necessary for me to once more return to the other Ichnographia.
Upon doing further research, i.e., going back to the University of Pennsylvania's Fine Arts Library to again scan the Ichnographia Campus Martius, more plan changes were indeed discovered, and, just as I had begun to suspect, the "change of plans" effected the Circus Hadriani, the Circus Domitiae, the Circus Flaminius, and the Circus Apollinaris. Thus, it is now evident that each of the major "changes of plan", between the Ichnographia Campus Martius that is widely published and the Ichnographia Campus Martius within the rare book collection at the University of Pennsylvania's Fine Arts Library, occur more or less exclusively within those buildings of the Ichnographia labeled "circus".
The plan above left is the Circus Hadriani as it appears within the commonly reproduced Ichnographia. Above right is the Circus Hardiani as it appears within the Ichnographia at the University of Pennsylvania.
The plan above left is the Circus Domitiae as it appears within the commonly reproduced Ichnographia. Above right is the Circus Domitiae as it appears within the Ichnographia at the University of Pennsylvania.
The plan above left is the Circus Flaminius as it appears within the commonly reproduced Ichnographia. Above right is the Circus Flaminius as it appears within the Ichnographia at the University of Pennsylvania.
The plan above left is the Circus Apollinaris as it appears within the commonly reproduced Ichnographia. Above right is the Circus Apollinaris as it appears within the Ichnographia at the University of Pennsylvania.
As the above plan comparisons indicate, the newly discovered circus plans engage directly with their neighboring buildings, thereby rendering a connected contextualism and demonstrating a more integrated urban planning methodology. The circus plans of the commonly reproduced Ichnographia on the other hand, albeit archaeologically correct, do not engage their immediate surroundings, and appear as though literally afterthoughts. Beside the already mentioned questions as to what these changes might mean and which set of plans came first, or what Piranesi's intentions in making the changes might have been, there is now an additional question as to why the changes were specifically and only applied to the Campo Marzio's six circuses.