This rectangular walled city is mentioned in both the Old and New Testaments of the Bible. It was fortified by the Romans, and subsequently embellished by local Christians with Byzantine-style mosaics over 100 years into the start of the Muslim Umayyad rule. Most of the city now lies in ruins, but there are several structures n its eastern part that have been excavated and restored.

Just outside the city walls is the recently unearthed Church of Saint Stephan. Its perfectly-preserved outstanding mosaic floor is the largest of its kind to be discovered in Jordan; second only to the world-famous mosaic map at Madaba. The mosaic depicts the images of 27 Old and New Testament cities of the Holy Land , both east and west of the River Jordan.

Just 2km north of Umm Ar-Rasas is the highest standing ancient tower in Jordan, rising 15m high with no door or inner staircase. Believed to have been used as a place of solitude by early Christian monks, today it is inhabited only by flocks of birds.