If you’ve traveled outside of the US this summer, a foreign language may not have necessarily been the biggest stress factor of the trip. Local customs are often what get us stumped.

Take a trip to the local pool, for example. Seems like an easy and universal-enough activity to not have to jump through the daunting hoops of cultural differences, right? Wrong. It can be an uncomfortable experience.

I am a native of the city of Auxerre, Burgundy, in France. It’s a lovely place of about 35,000 people, rich with medieval history.

It’s small, but it boasts many remarkable historical monuments, including a cathedral and an abbey from the Middle Ages and some ancient churches and chapels. It sits in the middle of the Burgundian hills, known for their excellent wines.

The city has another, more modern attraction that locals are proud of: its phenomenal public pool — or as it’s called there, the Nautical Stadium. It has four indoor heated pools with a jacuzzi, and three outside pools including an Olympic-sized one with a long, swirly slide. It is an extravagantly large — for its town — aquatic facility, built on the green banks of the river Yonne.

People travel from surrounding towns and villages to spend the day there, sunbathe on its beautiful lawns and snack at its eatery, when they are not swimming. You pay a small fee to get a bracelet which gives you access to the facilities. There's nothing tricky, except for the bathing suit rules.

You see, in most French public pools, there are strict regulations about the kind of bathing suit you can wear, and therefore share with others, in the water.

For illustration: (L) Not approved swimwear. (R) Approved swimwear. Credit: Adeline Sire

Simply put, where hygiene is concerned, your swimsuit cannot be something you could be found wearing outside the pool. That means no trunks, Bermuda shorts, T-shirts or anything that is not strictly meant for swimming.

Auxerre’s pool administrators say they do not want people to drag any dirt on, or under, their summer attire into the pool. So if you are going to join the masses of swimmers — all 2,000 of them on a busy summer day — you'll have very little cloth covering your own birthday suit.

Where else would you be told to wear something shorter and tighter, no matter your shape? Man, woman or child, you’ll have to wear some form of spandex, something tight, the kind Speedo makes. Something that often leaves nothing to the imagination — and it’s not to everyone’s liking.

If you are caught entering the pool with biking shorts, running shorts or trunks, lifeguards — turned fashion police — will blow the whistle and send you back to the lobby where you will be asked to purchase proper attire. This is where convenient vending machines come in.

In the Auxerre pool lobby, there are machines that vend soft drinks, sandwiches and espressos, and others that dispense anything needed for the pool, from ear plugs, soap, shampoo and goggles, to swimwear.

A vending machine at the public pool in Auxerre, France, dispenses swimsuits. Credit: Adeline Sire

A mannequin in swimming trunks with a big “forbidden” sign around its neck in the pool’s lobby is supposed to illustrate, for unsuspecting tourists, the kind of bathing suit that is acceptable. As a result, looking around, there is a certain repetitiveness to the swimsuit designs worn by men and boys.

There are four different designs in all, perhaps because that is all that is available at the vending machine or at the inexpensive sports store in town.

In the years since those regulations went into effect, I cannot remember hordes of disgruntled tourists getting outraged about this. But occasionally, one gets caught with his pants long (men more than women for obvious reasons) and is not happy about it.

The French have just gotten used to this, but for some visitors, the fact that municipal administrators have the authority to get you dressed to their liking — or un-dressed as the case may be — is completely infuriating. That is one of those unavoidable cultural quirks travelers must contend with in France.

As a resident of the United States, used to the uncompromising French swimsuit rules, it’s always disconcerting to me that anyone would be allowed to walk straight into an American public pool, from the street to the water, fully dressed, trunks over underwear, T-shirt over chest and sometimes with water shoes on.

That could make me love the French “no clothes — just Speedos” rules even more.

But perhaps there are no people on Earth prouder of their public pools than Icelanders. Iceland, where I just spent a few days, is rich with geothermal springs and big cities enjoy naturally heated outdoor pools. Because there are no chemicals in those pools, swimmers are expected to take a meticulous soap-and-scrub shower before entering the pool.

We were told that the rules are strictly enforced everywhere, and so visitors oblige.

The Blue Lagoon geothermal spa in Iceland. Credit: Adeline Sire

This was my experience recently at the Blue Lagoon geothermal spa near Reykjavik, where a very polite young staff lady looked on and directed all female visitors to shower in the nude before letting them into the hot spring. No one seemed to object. But then again, people were not told what to wear.

On your travels abroad this summer, what rules did you encounter swimming at local facilities? What surprised you? Let us know in the comments.