The Romans established the Decapolice , a league of ten cities in the land of northern Jordan , Syria and Palestine to facilitate the areas trad and to protect the far regions of their empire .

Four of the  cities lie in Jordan  : Philadelphia ( now Amman ) , Jerash the best preserved and most complete city of Decapolice , Pella and umm Qais .

The popular tourist attraction Pella is situated in the northern Jordan Valley . Here is ample evidence of early human occupation , with visible structures dating from the Roman , Byzantine and Islamic periods . It was during the Greco – Roman period , however that Pella truly prospered . The Byzantine era saw arevitalisation of Pella , as trad routes strengthened and local industries developed . Known in Arabic as fahl , Pella was the site of the famous Battle of Fahl , fought between  the Byzantines and the Muslim army led by khalid bin Al-Walid  and Abu Ubeida Amer bin Al-Jarrah in January 635 A.D.

Of comparable importance among the Decapolice sites is Umm Qais , Known in antiquity as Gadara . Renowned in its time as cultural center , Umm Qais was home to several poets and philosophers such as Theodorus , who described it as new Athens . Perched on a splendid hilltop , Umm Qais boasts an impressive colonnaded terrace of ruins of two theatres , over looking  the Jordan Valley  , the Sea of  Galilee and the Golden Heights . Jesus Christ performed the famous Miracle of the Gadarean Swine here .

Less than one hours drive north of Amman , nestled in a green and well-watered valley is the Greco-Roman city of Jerash . Known as the Pompeii of the east for its extraordinary state of preservation , Jerash is the largest and best –preserved Roman city outside Italy .

Built to honour the Emperor  Hadrian's arrival at Jerash in 129 A.D , the imposing triple-arched gateway greets you as you approach the city . within the remaining city walls of Jerash you can return to ancient times as you wander along colonnaded streets leading you towards original hilltop temples , spectacular theatres , plazes , baths and public squares . Especially in July this ancient community comes to life as the annual Jerash Festival of Culture and Arts attracts numerous visitors .

 

Tracing Islamic in Jordan , Jordan Tourism Board , page 14 .