In September 1980, Abadan was almost overrun during a surprise attack on Khuzestan by Iraq, marking the beginning of the Iran–Iraq War. For 18 months Abadan was besieged, but never captured, by Iraqi forces. Much of the city, including the oil refinery which was the world's largest refinery with capacity of 680,000 barrels per day, was badly damaged or destroyed by the siege and by bombing. Previous to the war, the city's civilian population was about 300,000, but before it was over, most of the populace had sought refuge elsewhere in Iran.
After the war, the biggest concern was the rebuilding of Abadan's oil refinery. In 1993, the refinery began limited operation & and the port reopened. By 1997, the refinery reached the same rate of production it was at before the war.