Onsen antics, Japan
Soaking in onsen (natural, mineral-rich hot springs) is a centuries-old health-giving tradition in which most Japanese immerse themselves. Onsen etiquette prescribes that the soaker washes thoroughly before entering the male or female bathing area. When walking around, you should cover your private parts with tiny towels and, once in, don’t make waves. Some onsen waters are also for drinking, so check before you gulp. And some don’t allow bathers with tattoos.

The 300 Club, Antarctica
Initiation to the 300 Club involves the wannabe member enduring a 149C (300F) change in temperature. Mother Nature takes care of the cold factor: Antarctic winter temperatures plummet to -73C. To make up the difference, nudies crank up the sauna then dash, steaming and screaming, to the geographic pole. The tricky part is trying to avoid running too hard, as the freezing temperature outside can damage lungs — not to mention exposed bits.

Forty Foot Pool, Ireland
The historic Martello tower, 5 miles (8km) south of Dublin, is a James Joyce museum that keeps a number of treasures, including a precious edition of Ulysses illustrated by Henri Matisse. Below the tower is a seawater pool mentioned at the close of Ulysses’ first chapter. In the tradition of Joyce celebrating “heroic commonplace”, many locals become everyday heroes by braving the skin-shrinking temperature of the sea sans swimming costume. But heed the sign: “Togs must be worn after 9am.”

Sizzling saunas, Finland
First shower, then swelter in an 80C hot box before streaking starkers outside and rolling in the snow or jumping into a small hole cut into the ice. Then repeat. In summer, gently flagellate yourself with wet birch branches, which stimulate circulation and smell nice.

The traditional wood-heated sauna was born of necessity, it being the only practical place to wash during long Finnish winters. Today there are more than 2 million saunas throughout the country, as well as a Finnish Sauna Society with 3,100 members.

Take a bath, Hungary
Budapest’s bountiful baths are fed by 123 hot springs. Locals have been taking in the combination of hygiene, health- giving properties and sociability since the 4th century BC. The health benefits of the mineral springs are instituted in the national health plan, which subsidises regular visits. Pad your way through labyrinthine chambers of various showers, pools (from tepid to hot), saunas and steam rooms. Wallow in the Art Nouveau surrounds: think cherub statues and sea-creature mosaics on the floor.

Bay to Breakers, USA
This historic foot race, traversing 7 miles of San Francisco’s peninsula, began in 1912 as a morale booster after a devastating earthquake. Many of the 75,000 participants run in costume (notables include Smurfs and a gang of Elvises); others choose to run sans costume. Nude runners are advised to wear a sun hat and shoes, plus the racing bib for those officially registered. Male runners are reminded that nature takes care of their floppy bits — genitals naturally tighten during exercise. Ladies: unsecured breasts may cause discomfort; wear a flesh-coloured bra as necessary.

Maslin Beach, Australia
Best Bum, nude Frisbee Toss and tug-of-war are not usual Olympic events, but at Maslin Beach’s Nude Olympics in South Australia, they’re the norm. Maslin Beach’s coloured cliffs afford it some seclusion, as well as providing the perfect viewing platform (provided you’re naked) for this event, held annually in January. Australia’s first nudist beach, Maslin, near Adelaide, was officially declared “unclad” in the late 1970s.

Tiergarten, Germany
A section of this stately park, bang in the centre of Berlin, is reserved for nude sunbathing. Once a hunting reserve for royalty, this section of the park is now something of a hunting ground for the mostly male sun worshippers looking for more than an all-over tan. Getting nude in the centre of the city is thrilling only in summer, otherwise just chilling.

Reproduced with permission from Lonely Planet Bluelist (Lonely Planet Publications, £14.99).

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