概要
Jerash lies in a well-watered valley in the hills of Gilead, about 48 kilometres north of Amman, the modern capital of Jordan. The ancient city of Gerasa was one of the cities of the Decapolis, a loose league of Hellenised cities east of the Jordan. Although a settlement existed here in earlier periods, the city was refounded as a Greek polis in the Hellenistic period — possibly under Seleucid auspices in the 2nd century BCE, when it bore the formal name Antioch on the Chrysorrhoas ("the Golden River"). It came under Roman control with Pompey's campaigns of 63 BCE and entered its period of greatest prosperity under Roman rule.
The city flourished from the 1st through the 3rd century CE, enriched by trade and by the agricultural wealth of its territory. Its prosperity was monumentalised in an ambitious building programme financed by local elites. A visit by the emperor Hadrian in 129–130 CE prompted the construction of a triumphal arch — Hadrian's Arch — at the southern approach to the city. The civic centre is laid out along a colonnaded cardo maximus, the main north–south street, paved and lined with hundreds of columns and still showing the ruts worn by ancient cart wheels. At its southern end lies the city's most distinctive monument: a great oval plaza, the Oval Forum, surrounded by an unbroken colonnade of Ionic columns — an unusual and elegant solution to linking the main street with the Temple of Zeus on the hill above.
Gerasa was lavishly supplied with public buildings: the South Theatre (seating around 3,000) and North Theatre, the monumental Temple of Artemis (the city's patron deity) raised on a vast terrace and approached by a grand staircase, nymphaea (ornamental public fountains), baths, and a hippodrome where chariot races were held. In the Byzantine period the city remained important and acquired more than a dozen churches, many paved with elaborate mosaics, several built from materials scavenged from the now-declining pagan temples.
The city declined after the Persian and Arab conquests of the 7th century, and was devastated by the great earthquake of 749 CE, which toppled much of the standing architecture. Subsequently abandoned and gradually covered by soil, Gerasa was largely forgotten until the German traveller Ulrich Jasper Seetzen identified the ruins in 1806. Systematic excavation began in the 1920s and has continued since, exposing one of the most complete Roman urban ensembles in the Near East.