CASTLE Rock is one of those isolated places treasured by locals but unknown to most others.
But this beautiful beach between Clontarf near The Spit and Grotto Point can also be a place of great danger.
Children who learned to swim in Clontarf pool in the 1950s and 1960s were always scolded by parents if they were seen swimming outside the pool - and with good reason.
The six most recent fatal shark attacks in Sydney all took place in Middle Harbour - two in Bantry Bay in 1942, one off Wyargine Point in 1955, one in Sugarloaf Bay also in 1955, one near Roseville Bridge in 1960 and one in Sugarloaf Bay in 1963.
In 1999 a 3.5m bull shark was caught off Castle Rock and taken to the Sydney Fish Market, where it fascinated those who saw it.
But the warnings about sharks at Castle Rock have been there for more than 100 years, as a report in the Daily Telegraph in 1908 highlights.
"The familiar old saying, 'once bitten, twice shy,' although usually applicable to the victims of the lesser carnivora, is not of much use where sharks are concerned in the biting, and in most cases it is better to be modestly shy before being bitten at all.
"These remarks are made apropos of the bathing season, which has now commenced and bathers, particularly in the harbour, will be doing themselves a good turn by observing a timely word of warning.
"On Sunday last a couple of monsters were seen lazily swimming around the rocks near Castle Rock, Middle Harbour.
"Their appearance scared a number of bathers, who just left the water in time to escape the notoriety of being the first victim of the season."
On Monday this week, a juvenile great white shark was rescued after it was seen floundering on the shore at Manly Beach.
The shark was rescued and carried to the rock pool at Fairy Bower, where it remained until staff took it to Manly Sea Life Sanctuary.
After a night recuperating at the aquarium, the shark was released into the ocean on Tuesday.
Whether it will be so welcome at Manly when it is an adult is a moot point.
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