Winter in Sydney is mild. It's a fact that is widely acknowledged by both its inhabitants and visitors. But that doesn't stop most of us grumbling about the temperature some days, when it's hard enough to extract ourselves from the warmth of our beds, let alone face the outdoors.

Some of us, however, laugh in the face of the cold, stripping down to take refreshingly chilly swims in some of Sydney's beautiful unheated outdoor pools and sea baths. But why on earth would anyone subject themselves to such an activity? Swimming in the winter is famously supposed to help boost the immune system, stimulate blood circulation and speed up your metabolism. Some even claim that winter swimming is relaxing. In Sydney, the winter waters hover around 14 to 17 degrees on average, a far cry from the colder waters of northern and eastern Europe or China, where winter swimming is traditionally quite a popular form of exercise.

One of the most well known locations to go winter swimming in Sydney is, of course, Bondi Icebergs, where during the colder months, hundred of swimmers race in order to get or maintain membership into the club. The club dates back to 1929, when the local lifesavers wanted to keep fit during the colder months. Nowadays, a running joke amongst members is that Icebergs is a drinking club with a swimming problem. Benjamin, a regular Sunday swimmer and a full member, doesn't hesitate to make it clear that there are some mornings when he doesn't look forward to it at all. "Sometimes, I don't want to do it, not one bit. Even if I forget why the hell I'm in the pool in the middle of a race because it's so cold, when I get out at the other end, I feel like I've achieved something. It's brilliant."

Cremorne Point's Maccallum Pool is a much quieter, more informal affair than Bondi's Icebergs. In fact, locals are usually the only ones there. The narrow, 25-metre length perches on the edge of Sydney Harbour with stunning views of the ferries, the Harbour Bridge and the Opera House across the water. Marilyn, a local resident, comes down to Maccallum Pool and does laps twice a week "all year round, even in the middle of winter”.

“There are some days when the sun is out and the Harbour is sparkling, and I'm so cold that I chatter into the pool and start swimming as fast as I can to get my laps done,” she says. “Then I'll sit, wrapped up in my towel and soak up the sun with a hot drink in my hands and everything is as it should be, just for a minute."

Down by Coogee Beach is the beautiful and heritage listed Wylie's Baths, named after champion long distance swimmer, Henry Alexander Wylie. One of the first mixed gender pools in Australia, Wylie's is a huge source of pride for the locals and interlopers alike. Frequenting Wylie's is (the appropriately named) Henry, a Randwick resident who's been coming to the baths since, well, forever. "I remember in the 80s, there were only cold showers back then. Nowadays, lots of people wear wetsuits and whatnot when they go for a swim. Me, I'm in there in my Speedos, the only way you should do it!"

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With two winter months left, will you be taking the plunge?

Sydney’s Sea Baths

Bondi Icebergs, 1 Notts Avenue, Bondi Beach

Maccallum Pool, Milson Road, Cremorne Point

Andrew 'Boy' Charlton Pool, 1c Mrs Macquaries Road, The Domain

Dee Why Rock Pool, Oaks Avenue, Dee Why

Bronte Baths, Bronte Road, Bronte

Wylie's Baths, Neptune Street, Coogee

McIver's Baths, Beach Street, Coogee

Newport Rock Pool, Calvert Parade, Newport