Jerash - Cardo Maximus 05
The colonnaded streets of Gerasa are among the best preserved of their kind in the Near East. Although their orientation deviates from the strict Greco-Roman scheme, the usual designations of the main axes are used for them: Cardo for the central north-south connection and Decumanus for the two major transverse streets that cross the Cardo at right angles in the south and in the north.

Until the early 2nd century AD, the course of Gerasa's streets was based on the terrain and the traffic routes that developed over time. It was not until the city became part of Provincia Arabia, founded by the Roman Empire after the annexation of the Nabataean Empire in 106 AD under Emperor Trajan, that planned expansion and reconstruction began. As far as possible, the older street network has been overlaid by a rectangular (orthogonal) grid 

The 800 m long Cardo does not run exactly from north to south as usual in the Hippodamian scheme, but slightly offset to the north-northeast because of the Chrysorhoas (Gold River, today Wadi Jerash). It was gradually developed into a representative processional and commercial road leading along the partly steep hills on the west side of the river valley from the North Gate in a straight line to the Oval Plaza and across it to the Sanctuary of Zeus Olympios, the most important cult site of Gerasa at that time (see also Oval Plaza).
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