Pick the incongruity

Looking from Bradleys Head southwards across the Harbour to Double Bay but there’s an inconsistency here. If you haven’t spotted it, you’re probably not going to - it’s the Doric column.
It was one of six cast aside when the original Sydney post office was demolished in 1863 and having no better ideas at the time, they put one on Bradley’s Head, no doubt hoping nobody would notice.
It’s actually exactly one nautical mile from the Martello Tower at Fort Denison so was used for many years in sea trial measurements.
We were hoping to return home tomorrow but that may not be the case - to be continued.