Resources Minister Martin Ferguson said the end of the refinery wouldn't jeopardise Australia's energy security or affect fuel prices, heading off the Opposition by noting that the unpopular new carbon tax hadn't been a factor in Caltex's decision.
While the closure will end refining on land the National Trust said was the equivalent of the United States' Plymouth Rock, it will not be returned - as advocates long urged - to its natural state and attached to the adjoining Botany Bay National Park.
Caltex intends to use the site for a new oil import terminal.
Until the company moved on to the Kurnell Peninsula, beginning a wave of industrialisation, the area had been regarded as an anthropological and palaeontological treasure trove.
Its 15,000-year-old sand dune system was occupied by the Gweagal clan of the Tharawal people, who had been living and fishing the Botany Bay area for 6000 years by the time Cook arrived on April 28, 1770.
In the 1950s, when the tiny European township was complaining of "primitive" living conditions - no water, no sewerage, and isolated completely in bad weather - the area held large Aboriginal kitchen middens and burial grounds. It was also one of Sydney's few remaining areas covered by unique native fauna.
When Cook landed, the indigenous locals had sent their women and children into hiding while two men stood their ground.
One grabbed a shield after being struck by musket shot, and the pair launched spears at the English landing party. They fled after a second shot.
Cook spent eight days rewatering HMS Endeavour and surveying Botany Bay, while botanists Sir Joseph Banks and Daniel Solander collected specimens.
Crewman Forby Sutherland died during the stopover, the first British subject to perish in Australia and the first European to be buried in New South Wales.
Caltex's plans in 1952 to spread a refinery over this history outraged conservationists, scientists and historians, who formed the Kurnell Peninsula oil refinery protest committee to fight the proposal.
National Trust vice-president Annie Wyatt was moved to try to enlist Eleanor Roosevelt, widow of wartime US President Franklin Delano Roosevelt, to the cause.
"I plead with you to use your great influence to prevent this act of irreparable vandalism," she wrote.
None of this influenced the state government. Eager for industrial development and supported by Kurnell locals who described the area as a "barren wasteland", it gave the go-ahead.
Now, 56 years since the refinery started operations, history has taken its revenge.