At Umm Al Nar, Arabic for "Mother of Fire", Abu Dhabi oil is heated to 500°C and hotter.
The refinery, 25 kilometres from the capital's centre, turns crude into gas oil, jet fuel and other hydrocarbon products.
When it opened in 1976, it was the first refinery in the UAE and could handle only 15,000 barrels per day (bpd) of crude.
Several upgrades have brought Umm Al Nar's capacity to 85,000 bpd, and it has diversified into functions such as blending lubrication oil, and turning the deadly sulphur that laces certain types of oil and gas into granules that can be safely transported.
Umm Al Nar island is also home to archaeological ruins discovered more than half a century ago by geologists from Abu Dhabi Marine Operating Company, the emirate's offshore oil producer.
Later, between 1959 and 1965, Danish archaeologists digging there found about 50 ancient tombs decorated with carvings of camels and oryxes.
