If you are reading this in the U.S., brace yourself.

In France, all employees get five weeks of paid vacation per year.

Five weeks. More than a month. And that does not include one-day public holidays, which can reach double digits in a given year.

We know about France and its summer vacations because we live in the south, about 30 minutes from the Mediterranean Sea, where plenty of sun is dependable and vacationers come chasing it. Most of them live in the northern half of the country, which can be gloomy even in the summer.

Catering to millions of internal tourists is a big industry, in France, and a significant source of revenue for businesses in the south.

Tourists will need to be fed and housed, unless they are camping (and more than a few do) and entertained.

The trouble with those five weeks off is that, historically, the French, like most Europeans, prefer to take several of them in August, thank you very much.

However, it does not make sense to have the whole of the country vacationing in the same month, so in recent decades France (at least) has spread out the “high” season to include most of July. (Yes, revolutionary.)

And observers have noted that the folks who travel in July are not quite the same as those who hit the beach in August, leading to epic traffic jams, especially on the north-south routes, on freeways rarely more than three lanes wide, and with every second vehicle some sort of camper/RV.

These separate sets of tourists have their own names, in French. The July people are known as Juilletistes (zwee-eh-teests). The August people are known as Aoutiens (oo-tee-ins) — based on the names of the two summer months.

And let the stereotyping begin!

Europe society tends to be very formal when it comes to the rhythms of life. August vacationers believe they are demonstrating their civic pride by taking off the traditional month.

However, the July folks have come to realize they enjoy advantages, even if they are considered not quite normal, perhaps even not quite patriotic, by their August brothers.

July people note that the resorts are less crowded, housing is often cheaper and they tend to be able to skip whatever projects are going on back among those still working the 35-hour work week, in Paris.

Meanwhile, August people suggest the July people are a bit shiftless because the latter cadre counts on getting back to “work” when most of their colleagues are absent, creating a month they can cruise through.

The Wall Street Journal took a look at this July/August thing recently, and some of the July people conceded it can be a bit weird to work in August, because phones and emails go unanswered, and the north (well, Paris) becomes overrun by foreign tourists, something none of the French really like.

Meantime, the July people think August people are too rigid, stuck in the old ways, even when it costs money and means bigger crowds at the resorts/beaches. (We made a trip over to our favorite beach, last August, and a very long and deep belt of sand was packed by so many people it freaked us out and we almost immediately left. It was awful. The folks crowding the strand probably figured it was always like that.)

August people, then, miss the comparatively less overwhelmed restaurants and theme parks and camp sites and sea-facing apartment buildings that are available in July.

This patterns leads to inefficiencies on the road, too — and a high fraction of tourists in our area (the Languedoc) or further east, on the Cote d’Azur, all arrive and depart on the same days, making for epic traffic jams.

The headline on the WSJ story is “What happens when all of France takes vacation? 438 miles of traffic.”

What happens is that the July people and August people try to occupy the same handful of freeways on the first Saturday of August — when the Juilletistes head home and the Aoutiens head out.

French TV documents this mess, and has codes for how busy traffic will be. Calling the road condition “black” means it is going to be a long, tedious drive.

One might think it would work out, the July people heading one way and the August people on the other side of the same freeway, going the other direction … but that does not take into account regular traffic in both directions, jams around toll booths and overcrowded rest stops trying to handle the streams of people heading in both directions.

The French understand this, of course, and how it would make more sense, in a world where tradition meant less, to spread out the tourist season … but a complicating factor is that school calendars hamstring France. Kids get out of school in the first week of July and have to return the first Monday of September.

That leaves the “shoulder” months of June and September deliciously open to those of us without kids in the house. Most vacation-oriented businesses remain open through September, and it is easy to pop on down.

By October, the vacation season is done. Those three-mile stretches of white-sand beaches? Left to a handful of seniors and their dogs, soaking up the late summer sun. That nearby business strip of pizza and burger and ice cream vendors? Shuts down for the year. With the bars and swimsuit shops and trinket salesmen also locked up. And the row upon row of beach apartment rentals — shut up tight until it starts over again next year.

So, three weeks … what do they do with the other two weeks off? If the summer is the beach, the winter is two weeks of … skiing!