With this is connected the fact, that for purposes strictly urban, such as the distribution of the introduced water, the inhabitants of Rome were divided into the inhabitants of the city proper (-montani-), and those of the districts situated within the general ring-wall, but yet not reckoned as strictly belonging to the city (-pagani Aventinensis-, -Ianiculenses-, -collegia Capitolinorum et Mercurialium-).( 13) The space enclosed by the new city wall thus embraced, in addition to the former Palatine and Quirinal cities, the two federal strongholds of the Capitol and the Aventine, and also the Janiculum;( 14) the Palatine, as the oldest and proper city, was enclosed by the other heights along which the wall was carried, as if encircled with a wreath, and the two castles occupied the middle.
The work, however, was not complete so long as the ground, protected by so laborious exertions from outward foes, was not also reclaimed from the dominion of the water, which permanently occupied the valley between the Palatine and the Capitol, so that there was perhaps even a ferry there, and which converted the valleys between the Capitol and the Velia and between the Palatine and the Aventine into marshes.

The subterranean drains still existing at the present day, composed of magnificent square blocks, which excited the astonishment of posterity as a marvellous work of regal Rome, must rather be reckoned to belong to the following epoch, for travertine is the material employed and we have many accounts of new structures of the kind in the times of the republic; but the scheme itself belongs beyond doubt to the regal period, although presumably to a later epoch than the designing of the Servian wall and the Capitoline stronghold.

The spots thus drained or dried supplied large open spaces such as were needed by the new enlarged city.

The assembling-place of the community, which had hitherto been the Area Capitolina at the stronghold itself, was now transferred to the flat space, where the ground fell from the stronghold towards the city (-comitium-), and which stretched thence between the Palatine and the Carinae, in the direction of the Velia.

At that side of the -comitium- which adjoined the stronghold, and upon the stronghold-wall which arose above the -comitium- in the fashion of a balcony, the members of the senate and the guests of the city had the place of honour assigned to them on occasion of festivals and assemblies of the people; and at the place of assembly itself was erected the senate-house, which afterwards bore the name of the Curia Hostilia.