Fort Denison, formerly known as "The Rock" and "Pinchgut Island", is a
small fortified island in Sydney Harbour National Park in Port Jackson. The island was originally known by the
local indigenous people as Mat-te-wan-ye (meaning rocky island). The fort was built between 1855-1857 to
defend Sydney against a feared attack by Russian warships during the Crimean War (1853-1856).
After the arrival of the first Europeans in 1788, the island was used as a place for misbehaving convicts. Often
a convict would be left on the isolated island for a week of punishment with little food or water. Thus the name '
Pinchgut' was given to the island. In 1796, Francis Morgan (an executed murderer) was left hanging on a gallow from
the highest point on the island as a warning to convicts and members of the colony.
In 1839, under the cover of night, two American sloops and five warships arrived in Sydney Harbour unannounced.
Their actions highlighted the weakness of Sydney's defences and resulted in the Governor ordering the building of a
level gun battery on Pinchgut island. The battery was completed in 1842 using convict labour (of course).
The Russians Are Coming
Following the outbreak of the Crimean War in the 1850's, Australia had
great fears that Russia would attempt to attack British colonies in the pacific regions. France and America
were also considered a potential threat. A decison was made to build a fort consisting of a martello tower,
gun battery and barracks on the island. Eight thousand tonnes of sandstone was used to build the fort. It
housed fifteen cannons; two ten-inch, one eight-inch and twelve 32-pounder cannons. The island was renamed
Denison, after the Governor of New South Wales at the time, Sir William Denison. Ironically the fort was
completed after the Crimean War had ended.
Guns of Fort Denison
The 8 inch shell cast iron gun at Fort Denison was originally located on
the top of the Martello Tower on a traversing platform. The traversing platform allowed the gun to be fired in
any direction. The gun was removed in 1913 and replaced with a navigation light. In 1963 the gun was restored
by the Maritime Service Board and mounted on a new platform. The main guns of the Fort were 32 pounders which
were designed to fire solid 32 pound cannon-balls. Both the eigh-inch shell guns and the 32 pounders had a
similar range of approximately 1,700m. However the eight inch shell gun used hollow shells which were less
accurate with distance and didn't have the same penetration power as that of the cannon balls. The gun shells
were better at close ranges due to the explosive filled shells that were deadly against wooden warships.
Things You May Not Know About Fort Denison
The island was manned by the British Royal Artillery until 1869 when the
New South Wales Naval Brigade took over the watch tower. By the 1870's the fort was abandoned as a military
Fort Denison was one of the last Martello Towers to be built in the world and
is the only one in Australia.
In 1906 the One O'clock Gun was transferred from Dawes Point to Fort Denison. The One O'clock Gun was used to
assist navigation of sea-going vessels and was fired everyday so sailors could set their ship's chonometers
correctly. The firing of the gun ceased during World War II but resumed again in 1986.
In 1942 a Japanese submarine entered the harbour and was fired upon by an American cruiser the USS Chicago
resulting in the tower being hit. Fortunately no major damage was done.
Tide readings have been recorded from the island since the 1860's and today the tide information is sent via
satellite to the Bureau of Meterology in Melbourne.