MIRABILIA URBIS. - The M. contain notices concerning the most notable Roman and Christian monuments and their vicissitudes, elaborated by grammarians and scholars according to identifications and traditions that are not always accurate and very often legendary. In their formation they reflect an Ottonian historical climate, when, with Otto III, the awareness of the imperial function of the Urbs seemed to reawaken in the Roman people.
In the climate of the renovatio Imperii there is talk only of claims to rights still alive and operative in the conscience of the Roman people; and the ancient ruins no longer constitute a decorative backdrop, where, with the splendor of a suggestive attraction, the ceremonies of the coronations of popes or kings took place, but assumed the appearance of eloquent witnesses of rights transmitted down through the centuries. The idea of the Empire thus remained almost naturally connected with the traditions of Rome, and in the Romans the awareness of their imperial destiny revived, through concrete and determinate juridical reasons. The immense success that these M. can boast lies in their perfect adherence to the spirit of the age, and in the skillful fusion of the two elements, realistic and poetic, which arose in the form of legend to reconcile the prestige of Roman greatness with the work that

(from R. Valentini - G. Zucchetti, Codice topografico della città di Roma, III, Rome 1916, pl. 1) MIRABILIA URBIS - Page of the "Codice Lochis" (end of the 12th century). Bergamo, formerly the property of Count C. Lochis.
Providence reserved for such power. This premise explains the adaptation of the M. as a guide for pilgrims, flocking from all over the world almost to the cradle of Christian traditions, and for seeing those monuments that, through legend, were linked to the arcane dispositions of Grace.
The oldest redaction of the M. is contained in the Lib. Politicus of Benedict the Canon, written between 1140-43. From the topographical aspect one can see in the M. a periegesis, followed in a determinate order: from the Vatican past Castel S. Angelo to the Campus Martius, then to the Capitoline, then descending from the Fora to the Arch of Titus, crossing the Roman Forum. Having reached the Palatine, one descends to the Colosseum, then, by way of the Aventine, to the Circus Maximus, to the Caelian, to the Lateran, to the Esquiline, to the Viminal, to the Quirinal, and, again, to the region of the Circus Maximus, to end once more near Castel S. Angelo, keeping to the left bank of the Tiber. The periegesis ends with a visit to Trastevere, to the Tiber Island, proceeding beyond the Porta Appia. Then the M. are found again in the collection of Bosone (1154-81), in the collection of Albino (c. 1190), in the Liber Censuum of 1192; then in the Graphia aurea Urbis composed between the end of the 10th century and the first half of the 11th, whose author drew notices also from the Bible, from the Chronicle of St. Jerome, from the Constitutum of Constantine, from Vegetius, from Isidore, from Severus, from Paul the Deacon.
The Miracole de Roma vulgarize, around the middle of the 13th century, the oldest text of the M. with additions taken from the Regionaries and from the Graphia. To the end of the 12th century or the beginning of the 13th must be assigned the treatise of Master Gregory
De mirabilibus urbis Romae, relating almost entirely to pagan monuments. A different distribution of the material is found in the collection De mirabilibus civitatis Romae of Nicolas Rosell, called the Cardinal of Aragon (1314-62).
Bibliography2 works
Roberto Valentini