We noticed this strange pillar standing in Sydney Harbour at Bradleys Head. It looks like a public artwork about the dangers of global warming and rising sea levels. Or maybe the ruins of an old waterside funfair.
But in fact it is one of six Doric columns that used to adorn the old GPO, built in 1847 and demolished in 1863. This column was placed in Sydney Harbour, exactly one nautical mile from the tower on Fort Denison, and used for sea trial measurements.