On a recent trip to Athens we were somewhat taken back to learn that the little plastic bucket next to toilet was for the disposal of toilet paper — because of the age of the city's plumbing systems, there was no flushing down the toilet permitted.

Signs in the lobby and throughout the apartment warned of the dire consequences of ignoring this rule. Our vacation rental was fairly modern, not an ancient lodging from the time of the Acropolis, so were somewhat surprised at this restriction. It turns out that this is a common restriction throughout Greece. We've seen this method in other parts of the world, but hadn't expected to find it in an otherwise modern European country.

Bathroom configurations and etiquette vary around the world, so it's wise to be prepared. We discovered a website that is cleverly called "Where do I put the paper?" at WhereDoIPutThePaper.com. With somewhat cheeky humor (yes, we couldn't resist that one) it informs travelers about proper toilet etiquette in 195 countries. Of all the websites we have found on this subject, this is one of the most useful. It turns out that in several countries you need to "bin" the paper.

In many Asian cities, toilets have approached an art form, where a computerized keypad offers options for a personal rinse and dry after flushing — sort of a toilet and bidet combined. However in rural Asia (and some parts of Europe), squat toilets are common, essentially a hole in the floor with foot pads on either side — be sure to step aside before you flush! Signs on some modern public toilets ask that people not squat on top of the seat. Experienced travelers also know to carry a small packet of tissues, as toilet paper is rarely available at rural locales.

Regardless of the plumbing, it can be a challenge to find a "friendly" toilet in an unfamiliar location. When Michael was a child, his mother taught him to seek out restrooms in fancy hotels. She'd say, "Just act like you belong there." (A skill he has to this day.) Fortunately, there are now apps for your smartphone to find toilets — we like the one that's aptly named  "Flush." It calls up restaurants, bookstores, shops, and other convenient locations.

Here's a primer on the type of toilet you are likely to see on your travels:  bfplumbingbayarea.com/blog/toilets-around-the-world. Knowing before you "go" can help smooth your experience overseas.

Larissa and Michael Milne have been full-time global nomads since 2011. Follow their journey at ChangesInLongitude.com.