The islands of Sydney Harbour stand like lookouts on one of the world’s most attractive waterways -- reshaped by the demands of war. But where there used to be 14 islands dotting the busy harbour, only eight have avoided the growth of Australia’s biggest metropolis.

“Some people may not be aware that some of the coastline’s bulging headlands were originally islands,” explained Ian Hoskins, the official historian at the North Sydney Council and author of the book Sydney Harbour: A History.

The best known of Sydney’s vanished islands is Garden Island, which was used as an offshore farm to feed a fledgling penal colony in the late 18th Century and is now one of Australia’s most important navy bases.

In 1942, after a military dry dock for naval boat repairs joined the island to Sydney’s southern shoreline, Garden Island witnessed an attack that brought terror to a nation in fear of invasion. A Japanese midget submarine sank the moored accommodation ship Kuttabul, killing 21 Australian and British sailors during WWII. The northern part of this historic treasure is now public parkland, only reachable by ferry and peppered with historic buildings and naval installations. It is a popular picnic spot too.

Other islands that lost island status when developers joined their landmass with the mainland include Darling Island, which became part of the mainland in the late 1840s and later became the base of Darling Harbour, a popular restaurant and entertainment hub in the suburb of Pyrmont. Little Bennelong Island, a tiny hummock of land, was appropriated by the mainland in the 1820s and now makes up the tip of Bennelong Point, home to the Sydney Opera House. And Glebe Island, an industrial area in the suburb of Balmain, joined the mainland in the 1860s and now acts as a cargo storage area for freighters. In the case of Glebe Island, developers filled the gap between the island and the mainland with rocks to create a connecting causeway.

“My favourite island is, in fact, not an island,” Hoskins said. “[Berry Island] is so easy to get to and is joined [to the mainland] by this isthmus of lawn, but once you’re there, it is this wonderful angophora forest. There are various Aboriginal sites and you can see grooves in the rock where they would have sharpened spears… and you can look out through the Sydney red gum trees and get a sense of the pre-European harbour.”

The islands that remain
Through the mist on a damp day, a Captain Cook tour boat ferried soggy tourists to Fort Denison, a rocky outcrop of an island that once housed an early convict prison. To boost Sydney’s maritime defences during the early years of colonization, the tiny island was flattened and Australia’s only Martello-style fort was built, similar to those that dotted the coast of Britain in the mid 19th Century, with very thick sandstone walls to absorb cannon fire. The highly recommended Fort Denison Cafe and Restaurant serves Australian cuisine with a Mediterranean twist and for those with very deep pockets, the island affords a front row seat to arguably the world’s finest New Year’s Eve fireworks display. Only reachable by boat tour, Fort Denison is one of Sydney’s gems, with spectacular views of the opera house and the old coat hanger bridge that spans one of the world’s most photogenic harbours. Even on a damp day, visiting is a treat.

“It is quite an iconic image for Sydney Harbour,” explained Bernie Courtenay, the Captain Cook cruise boat skipper. “It was a little island when the First Fleet [of settlers] arrived here [in 1788]. They had no use for it except as a place of isolation for reoffending convicts. During the 1840s, because of fears of invasion by privateers and foreign navies, they decided to fortify the island. You can [still] walk around Fort Denison and quite imagine yourself back in Crimean times.”

The other slice of real estate that has been radically altered is Cockatoo Island, which was a shipbuilding hub until the early 1990s. Today, it has been reborn as a cultural haven, with cavernous warehouses that host concerts and exhibitions, including the spectacular Biennale of Sydney, a visual arts festival. Visitors can bed down in dedicated luxury campgrounds or in heritage holiday homes, and Sydney’s largest island at 17.9 hectares is reached by ferry, water taxi and private boat. Or, for the intrepid, this island is one of the only ones in the harbour that can be reached by kayak.

Other smaller dots on the west side of Sydney Harbour, such as the private island of Snapper and the navy base of Spectacle Island, are not generally open to the public. But they can be seen by ferry on the Balmain West-Birchgrove Service from Circular Quay. Quaint summerhouses dating back to the 1920s bring visitors to Rodd Island, a former biological research station nestled in Iron Cove near the Sydney suburb of Rozelle. Today, the 0.5-hectare island can be reserved for weddings and other functions, is a popular picnic site and can be reached by water taxi.

Shark and Clark Islands, located off the harbourside suburb of Darling Point and Rose Bay respectively, became dedicated recreational areas as early as the 1870s and are now great places to watch the boat traffic in Sydney Harbour. The island’s picnic areas offer stunning views across Sydney Harbour, and it is a priceless feeling to sit on a tiny speck of land in the middle of one of Australia’s busiest harbours, watching the ferries and pleasure boats glide past the diamond-crusted waters.

“Most of us feel like we want to go and sit on an island and get away from it all,” said Judy Bennett, a commentator for Captain Cook Cruises. “People go to Shark Island for weddings. It’s very romantic. There aren’t too many people out there.”

Goat Island, located just west of the Harbour Bridge, is known as the “Eye of the Harbour” as it commands magnificent views of Sydney’s greatest natural treasure. It is also a place revered by Aborigines, who conducted spiritual ceremonies on the rocky outcrop until the early 19th Century. The island has had a varied career over the years, serving as a convict stockade, explosives store, police station, boat yard and film set. Relics of Goat Island's convict origins remain, including a seat carved out of stone by Charles Anderson, an inmate who was sentenced to be tied to a particularly large slab of the island for two years.