The oil refinery and petrochemicals facility at Grangemouth is home to Scotland's only crude oil refinery and produces the bulk of Scotland's fuels.
Current owner Ineos has announced £1bn worth of investment, with £850m being spent in Scotland.
The 1,700-acre site supplies 70% of the fuel to Scotland's filling stations as well Northern Ireland and the north of England.
It also provides power to the Forties oil pipeline, which brings oil and gas ashore from the North Sea.
BBC Scotland News takes a look back at the site's history.