Cork Harbour is often described locally as “the second largest harbour in the world”. For a long time, I’ve been somewhat sceptical of this claim, so I decided to compare its size to other harbours using the MAPfrappe website. With this website, you can quickly compare locations with other sites around the world. I used it a while ago to compare well known islands to Ireland.

First of all, here is Cork Harbour. It’s a natural harbour, dominating a region of 22 km  x 16 km east of Cork City. A very rough estimate of its water-surface area is about 70 sq km, although I am open to correction on this. The land area in the centre is Great island, home to the town of Cobh and connected to the mainland by two bridges, one road, one rail. Less than two kilometres separate the headlands as it meets the sea, making it by any reckoning, a fine, strategically important natural harbour. Its considerable depth in many places allows large ocean going vessels – tankers, container ships and liners – to enter and depart with ease.

CH - Cork Harbour

It’s a beautiful, impressive and fascinating area, full of history and natural beauty. But is it one of the biggest in the world?

According to Wikipedia, its rivals are Sydney Harbour, Halifax Harbour in Nova Scotia and Poole Harbour in Dorset. Let’s see how they compare.

Poole Harbour, Dorset UK

Poole Harbour, UK

Aw look. How cute. Cork Harbour (silhouetted like a horned monster petitioning mariners just outside) wins this one. Poole, incidentally, also thinks of itself as one of the largest natural harbours in the world. I hate to break it to you, guys.

Halifax Harbour, Nova Scotia

Halifax Harbour

Cork harbour wins this one too, even if you were to be generous and start at McNabs island.

Port Jackson / Sydney Harbour, Australia.

Port Jackson

Y’know, I was surprised at this one, because most Corkonians will gladly concede that Port Jackson is larger. It doesn’t look like it here. The main open water areas are at least comparable.

After, these three, the assessment is.. maybe. But then, are there not other spaces that could  rival Cork in size? New York, San Francisco or Rio perhaps?

New York City

New York City

It’s close. Very close. I’d nearly give New York Harbour the edge. Interestingly, the mouth – Verrazano Narrows – is so similar in size to Roches Point / Crosshaven we should really have our own suspension bridge, just for the crack.

Rio de Janeiro, Brazil

CH - Rio de Janeiro

Rio’s Guanabara Bay looks to me like a proper harbour and it’s clearly bigger than our own – in fact you could possibly fit the whole of Cork Harbour into it.

It gets worse.

San Francisco

San Francisco

Oh this is not good. Cork Harbour looks tiny. And they have a suspension bridge at the mouth of their harbour too.

Oh, and we forgot:




Auckland Manukau, NZ

Auckland Manukau

or, staying in New Zealand:

Kaipara Harbour, NZ

Kaipara Harbour, NZ

Whoa. Still though, we’re big for Europe, right? Right?

I give you:






and finally,



Folks, we need to take a long, good look at ourselves. Even if we are only the second largest harbour “by navigable area” (a claim I suspect given the sizes of Rio, San Fran and Tokyo, or we want to be pernickety about what harbour really means, we have to content ourselves that the claim “2nd Largest Harbour in the World” is dodgy. Seriously dodgy.

Still beats Dublin, though.