The region boasts of ancient and active urban centres, some founded or rebuilt during the reigns of Ptolomy II and Ptolomy III in the third century B.C. (e.g. Philadelphia, present-day Amman, Gadara), or under the Seleucids in the second century B.C. (e.g. Pella and Gerasa). The Decapolis ("the ten cities") formed a Greek cultural pole in a Semitic setting. The Pax Romana, beginning with the conquest of Pompey, ushered in a 500 year period that favoured trade, construction and general prosperity.

For Jordan, the Roman period meant, above all, a reorganisation and restructuring of the territory. From the year 106 A.D., just after Nabatea was annexed and Trajan had organised the province of Arabia, regional development was orchestrated on a large scale. There was not only an urban development plan, but a rural plan as well, although the steppes and the desert zones were largely overlooked.

  New major roads were laid out to make travel both faster and more convenient (the Via Nova Traiana gave Bosra a direct link to the Red Sea), while old highways were improved, standardised, maintained and supervised. Today, all over Jordanian territory, numerous vestiges may be found on these ancient roads (e.g. milestones and supervision structures). To put it simply, the new province's roads were aligned with the technical standards of the Empire.

The cities and their monuments present the best evidence of this regional development. Jerash is no doubt the best known urban site of the region. Its gridiron layout was not, as was long believed, the work of some Hellenistic-period disciple of Hippodamus, but was in fact, a much later innovation (second century A.D.) superimposed on an Oriental urban framework. The cardo, or north-south axis, typical of Roman cities, led straight to the main sanctuary from the city gates. Rather than being a real street, it was both a processional route and a shopping lane. In Jerash, as elsewhere, this western dress was a mere façade that barely hid the reality of a profoundly oriental city with oriental concepts. The population was thoroughly Semitic, as witnessed by the anthroponomy of the region.