The ruins of ancient Gerasa are the reason to come to Jerash. The site is vast — allow at least three to four hours, more if you want to read the interpretive panels and photograph seriously. The main circuit from the Hadrian's Arch entrance north through the Oval Plaza, the colonnaded Cardo, the temples, and the theatres covers about three kilometres of walking.
The modern town of Jerash sits beside the ruins and offers restaurants and craft shops. A sound-and-light show runs in summer evenings for those who want to see the site in a different light.