If you hear someone yell, “Shut the door!” you’ve just broken what seems to be the only rule at Sydney’s diviest sauna (or was, before a renovation in February). And I absolutely mean “dive” in the dive-bar sense of the word. You know, those well-worn, kinda-shitty-but-kinda-great late-night drinking dens, but in this case it’s a well-worn, kinda-shitty-but-kinda-great humid timber box frequented by people who like to get a sweat on.

The sauna is part of Bondi’s Icebergs pool, one of the world’s most Instagrammed destinations. Thousands of photos have been captured of waves crashing into the historic pool and of tanned bathers frolicking in the cyan-coloured water. But most people don’t know that a semi-clandestine group of people regularly visit the attached 3.5-metre by 3.5-metre sweatbox to marinate.

Anyone can go. Entry to the hot house is granted with the price of pool admission ($8 for adults; $5.50 for children). It means sometimes it’s skin-on-skin, and not in the good way.

I reckon it can accommodate 15 people seated and 10 standing, a population milestone you don’t want to be involved in. Most people sit there gazing out of the windows, watching the blue water and impressive views to Ben Buckler. But then there are those who like to talk. Loudly.

There was one conversation started by a guy who looked like he could be a lawyer in the outside world. “Where can you get the cheapest schooner?” he asked, as if to no one. The question still caught the sauna’s attention. “Oh, that’s easy,” piped up a 30-something bloke – “Bondi Hotel”. A woman with an accent sitting opposite agreed, saying only last night she had acquired several jugs of its finest Hahn Super Dry for 10 bucks. “Nah, nah,” said a plump, red-faced old fella. “It’s Waverley Bowling Club. It’s $6.40, or $5.90 if you’re a member.” It was established this man knew what he was talking about – he just looked like he’d drunk more beers than any of us, you know?

“Salty old dudes” is a fair descriptor for most of the regulars at the Icebergs sauna. They’re there in the deep of winter doing laps and then thawing off in the steamer. Occasionally there’s someone who’s decided it’s the perfect time to catch up on their hamstring stretching. I mean, sure, go right ahead, but you are almost nude (nude!).

Dress code isn’t really a thing. A sign at the front door says: “No Towel, No Entry.” The only other rule more ignored in Australia is MPs’ dual-citizenship. Most men wear lycra undies, and the women skimpy two-pieces. No one bothers with shoes. There are rotund bellies, flat bellies, six-packs, snail trails, men with hairy backs, men with no hair, women with big boobs, the super fit, retirees, and lots of bronzed skin covered in beads of perspiration.

Some patrons clutch bottles, occasionally taking swigs of water to stay hydrated. One time, the son of a prominent Sydney restaurateur had beside him a couple small bottles of sparkling water. They were largely ignored – he was sprawled on a bench asleep. Or passed out, perhaps. When the cad came to, it was apparent he was drunk. He muttered something I couldn’t really decipher. It was noon on a Sunday.

But mostly it’s conversation everyone hears, even if they don’t want to. “I’m actually moving to Stockholm in March,” said a guy to a couple he bumped into. “Oh, that’s great, what for?” “I’m going to be working on some projects,” he said vaguely.

Yeah, sure.

Recently, a heavily tattooed guy chatted to a sauna acquaintance about relationships, parenthood and a brother going through a tough divorce. A newcomer to the conversation chimed in with, “So what you’re saying is never get married, never have children?”

“No, I’m not saying that at all. When you have a child it’s the most amazing thing, it’s a powerful, magical experience to go through as a human. It’s the human magic spell.”

Is it?

Yet for all its foibles, the Icebergs sauna is absolutely glorious, and unlike anywhere else in Sydney. Just like election day, a Bunnings sausage sizzle and airport security gates, it’s a great leveller, bringing together people of all walks to live harmoniously side by side for 10 or so minutes, sharing life lessons and advice. Unless you take too long to close the door – then you’re the worst person in the world.

“Shut the door!”

This story originally appeared in Sydney Print Issue 17.