The sources of our knowledge are twofold. In a few cases archaeological excavation has laid bare the paving of Roman streets or the foundation of Roman house-blocks. More often mediaeval and modern streets seem to follow ancient lines and the ancient town-plan, or a part of it, survives in use to-day. Such survivals are especially common in the north of Italy. It is not, indeed, possible to gather a full list of them. He who would do that needs a longer series of good town-maps and good local histories than exist at present; he needs, too, a wider knowledge of mediaeval Italian history and a closer personal acquaintance with modern Italian towns, than a classical scholar can attempt. But much can be learnt even from our limited material.[[68] ]
The evidence of the streets needs, however, to be checked in every case. It would be rash to assume a Roman origin for an Italian town simply because its streets are old and their plan rectangular. There are many rectangular towns of mediaeval or modern origin. Such is Terra Nova, near the ancient Gela in Sicily, built by Frederick Stupor Mundi early in the thirteenth century. Such, too, Livorno, built by the Medici in the sixteenth century. Such, too, the many little military colonies of the Italian Republics, dotted over parts of northern and middle Italy. Often it is easy to prove that, despite their chess-board plans, these towns do not stand on Roman sites. Often the inquiry leads into regions remote from the study of ancient history.
Fortunately, enough examples can be identified as Roman to serve our purpose. Some of these occur in the Lombardy plain where, both under the Republic and at the outset of the Empire, many 'coloniae' were planted full-grown and where town-life on the Roman model was otherwise developed. Not all these towns survive to-day; not all of the survivors retain clear traces of their Roman town-plan; in nine cases, at least, the streets seem unmistakably to follow Roman lines. Four of the nine date from early days; in the late third and the early second centuries (218-183 B.C.), Piacenza, Bologna, Parma, and Modena, were built as new towns with the rank of 'colonia'. The first three of these were later refounded, about 40-20 B.C.—whether their streets were then laid out afresh is an open question—and Turin and Brescia were added. In addition, Verona, Pavia, and Como won municipal status in or before this later date, though when or how they came to be laid out symmetrically is not certain.[[69] ] And there are other less certain examples.
Other instances, but not so many, may be quoted from south of the Apennines. At Florence, for example, and at Lucca 'coloniae' were planted full-grown and the street-plans still record the fact. At Naples, at Herculaneum, perhaps at Sorrento,[[70] ] proofs survive of similar planning. But the towns of central Italy were in great part more ancient than the era of precise town-planning, and many of them were perched in true Italian fashion on lofty crags—praeruptis oppida saxis—which gave no room for square or oblong house-blocks. In the period of the dying Republic and nascent Empire fewer 'coloniae' were planted here than in the north, while in much of southern Italy towns have in all ages been comparatively rare.
In the towns just noted we can trace many, though not all, of the original house-blocks. Usually the blocks are square or nearly so, as at Turin, Verona, Pavia, Piacenza, Florence, Lucca. Less often they are long and even narrow rectangles, as at Modena, and Sorrento, and above all Naples, and as usual it is not easy to understand the reason for the difference (p. 80).
Turin (fig. 15).
Of all the examples of Roman town-planning known to us in Italy, Turin is by far the most famous.[[71] ] Here the streets have survived almost intact, and excavations have confirmed the truth of the survival by revealing both the ancient road-metalling and the ancient town-walls and gates. Turin, Augusta Taurinorum, began about 28 B.C. as a 'colonia' planted by Augustus. Its walls enclosed an oblong of about 745 x 695 metres (127 acres).[[72] ] The sides are represented (1) on the north by the Via Giulio, in the western part of which the southern edge of the street actually coincides with the line of the Roman town-wall, while further east the Porta Palatina enshrines an ancient gate; (2) on the west by the Via della Consolata, and the Via Siccardi, the east side of which latter street seems to stand upon the Roman town-wall; and (3) on the south by the Via della Cernaia and Via Teresa, the north side of which stands over the Roman southern town-wall. (4) The east wall agrees with no existing street but may be represented by a line drawn through the Carignano Theatre and the western front of the Palazzo Madama, which contains the actual towers of the Roman east gate.[[73] ] The north-west corner, uncovered in 1884, is a sharp right angle. This feature recurs at Aosta and at Laibach (pp. 90, 116), both founded, like Turin, in the Augustan age, and seems to belong to that period; later, it gave place to the rounded angle visible at Timgad (p. 109) and in many Roman forts of the middle Empire.
Of the interior buildings of the town little is known. The Forum perhaps stood near the present Palazzo di Città, and the Theatre was traced in 1899 in the north-east corner of the town, occupying apparently, a complete insula;[[74] ] of the private houses nothing definite seems to be recorded.
But the street-plan has survived intact, except in two outlying corners. The town was divided up into square or nearly square blocks, of which there were nine counting from east to west and eight from north to south. Most of these 'insulae' measured about 80 yds. square.[[75] ] A few were larger, 80 x 120 yds.; these were ranged along the north side of the street now called Via Garibaldi (formerly Dora Grossa), which represents the Roman main street between the east and west gates—in the language of the Roman land-surveyors, the decumanus maximus. This street cut the town into two equal halves. The other divisions of the town were no less symmetrical. But, as there were nine 'insulae' from east to west, the main north and south street could not bisect the town. Indeed, the south gate seems to have had five house-blocks west of it and four east of it, while the Porta Palatina stands further west, with six blocks on the west side of it. The north and south gates, therefore, are not opposite.[[76] ] Whether this was the original plan is not clear, nor is the age of the surviving walls and gates quite certain; the bonding courses in some of the masonry of the walls does not seem Augustan. But the street plan may unhesitatingly be assigned to the first establishment of the town, about 28 B.C. Since, it has been extended far beyond the Roman walls. Nearly all modern Turin has been laid out, bit by bit, in imitation and continuation of the original Roman lines.