By September 18, 2019 Blog Comments Off

Sydney Harbour facts to know before your boat hire

Some little known facts to know about Sydney Harbour before your next Sydney Harbour boat hire.

Visitors and residents of Sydney delight in the natural and man made wonders of Sydney Harbour every single day, be it riding a ferry, attending a show at the Opera House, crossing the Sydney Harbour bridge, taking a scenic walk, or dining at one of the harbour-side restaurants. Perhaps it seems that everything the harbour has to offer is on display, but did you ever wonder if there is more than what meets the eye, or what is (literally) beneath the surface? Have a read through some of our favourite interesting facts about Sydney Harbour and you’ll have even more appreciation for this famous landmark next time you’re riding atop its waters. At East Coast Sailing we offer services including Sydney yacht hire or a boat hire on Sydney Harbour to experience this interesting city up close.

One of the most interesting, but least known facts about Sydney Harbour is that it has its very own official unit of measure to approximate its volume in water. The unit is aptly called a ‘SydHarb’ and is equivalent to roughly 560 gigalitres, which is over 500,000,000 cubic metres. If you can’t quite get your head around a SydHarb, it can be compared to the following: The amount of water that passes over Niagara Falls in two full days, 238,000 Olympic swimming pools, or 357 Melbourne Cricket grounds. For scale, a Melbourne Cricket ground is the largest stadium size in the country and seats 95,000 people, so imagine that multiplied by 357… that’s one SydHarb.

Within the one SydHarb of water in the Sydney Harbour, there are nearly 600 species of fish alone! Some of the common species include: Bream, kingfish, fan bellied leather jackets, blue swimmer crabs, moon jellies, and flat head. There is also a tube worm that lives on the sea bed. Beyond fish, there are over 3,000 species of sea life present around the Sydney Harbour waters, many of which, land-dwellers like us will never see. With Sydney Yacht hire, you can experience this amazing marine life up close and personal.

Sydney Harbour Boat Hire


The Sydney Harbour was originally a valley river estuary system carved into sandstone millions of years ago. It became the natural harbour it is now when the oceans rose 10,000 years ago and flooded the river. Read more about what it means to be a natural harbour here.

While the volume of Sydney Harbour is inexplicably vast, the depth is another story. While some deep holes have been discovered which go at least 45 metres deep, the seabed morphology is not at all uniform. For instance, some areas of the harbour are only 3 metres deep, but still contain shoals of fish. To get some perspective, if you’re looking at the Harbour Bridge, the distance from the water’s surface to the highpoint of the bridge is 134 metres, much higher than the deep areas beneath.

One of the main uses of the Sydney Harbour is for transportation to and from the city. Every single day, roughly 40,000 trips are made across the harbour, just on ferries. There are also four different bridges that allow travel over the Harbour by car or bus including: the Silverwater Bridge, the Gladesville bridge, the Ryde bridge, and of course the Sydney Harbour bridge.

Sydney Harbour Boat Hire


While modern day ferries are safe and reliable, there were many ships that didn’t make it across the Sydney Harbour once upon a time. There are now at least 30 shipwrecks beneath the surface of the harbour’s waters.  Many of them are intact, and you can even get a permit to dive down to them if you’re really curious. Often, after some time, marine life will inhabit a shipwreck and make it home.

Before European settlers arrived, the area where Sydney harbour is, was home to the Gadigal, Cammeraygal, Eora, and the Wanegal tribes. In 1770, Lt. James Cook sailed past the harbour on his way up the East Coast. He later named it after Sir George Jackson, which is why it is also known as ‘Port Jackson’ today. Sydney Harbour has a unique role in Australian history as the first place on the mainland for European settlement and colonisation.

If you’re visiting Sydney Harbour, boat hire will allow you to take in the shoreline of the Harbour which spans 322 km, and almost 80 kms of which has been reclaimed for various uses. Because of this reclamation, much of the shoreline has been altered from its original shape.

If you plan to visit Sydney in 2032 you can partake in the centenary celebration of the Sydney Harbour Bridge construction, which may include allowing the public to walk across the harbour! This would be the third time in history that a public walk is permitted. The first two times were at the grand opening, and at the 50 year anniversary. The bridge took 8 years to build with almost 1500 men, 16 of which died in the process, while 800 families were displaced to make way for its construction. Now, more than 150,000 vehicles cross this monument, and the Sydney Harbour beneath it, each day. 

Sydney Harbour Boat Hire


Feeling inspired by the history of the incredible Sydney Harbour? We offer Sydney Harbour boat hire to experience this historically rich city up close. If you’d like to get out and enjoy these famous waters, get in touch today and we’ll get you out there.