France runs on Central European Time: UTC+1 in winter, UTC+2 in summer (CEST). DST follows the EU standard. The clocks change on the last Sunday in March and the last Sunday in October, as they do across most of Europe.

This is, frankly, the boring part of the French time story.

The interesting part is that France is the country that gave us the single greatest literary meditation on time, longitude, and the relationship between movement and calendar. Jules Verne wrote it in 1872. The twist still lands.

Around the World in Eighty Days: the day that wasn’t lost

Phileas Fogg bets his friends at the Reform Club in London that he can circumnavigate the globe in 80 days. He and his valet Passepartout set off east: through France, through the Suez Canal, across India, through Hong Kong and Japan, across the Pacific, across the United States, back to London.

They return on what appears to be the 81st day. The bet is lost. Passepartout is devastated.

Then the realization: because Fogg traveled continuously eastward, he gained time with every longitude gained. Each day, as he moved east and the sun rose earlier, he was in effect living slightly shorter days. Over the course of eighty days, this accumulated to exactly one full day. Fogg had been keeping his journal as if each day were a full twenty-four hours, but he had actually moved a full rotation ahead of the sun.

He arrives back in London on the 80th day, not the 81st. The bet is won.

Verne wrote this story four years before the International Meridian Conference of 1884 established the Prime Meridian at Greenwich and created the framework for global standard time. The novel appeared at exactly the moment when educated readers were beginning to grapple seriously with what it meant for the earth to be round and for time to therefore be relative to longitude.

The International Date Line, which Verne did not yet have available as a named concept, is the mechanism that makes the Fogg twist work in reality. Cross it going east and you subtract a day; cross it going west and you add one. Fogg crossed the Pacific heading east, gaining a day in practice even though his diary did not record it.

France and its extraordinary timezone count

Metropolitan France is UTC+1 (winter) and UTC+2 (summer). But France also has overseas departments and territories spread across the globe, and the Republic technically contains more IANA timezones than any other country. This includes French Polynesia (multiple timezones in the Pacific), French Guiana (UTC-3), Martinique and Guadeloupe (UTC-4), New Caledonia (UTC+11), Réunion (UTC+4), Mayotte (UTC+3), Saint Pierre and Miquelon (UTC-3 to UTC-2 with DST), and several others.

The French state is a planetary operation. The sun never fully sets on the French Republic.

Paris: the meridian that lost

Before Greenwich became the world’s reference meridian in 1884, France used the Paris Meridian, running through the Paris Observatory (built in 1667 under Louis XIV). French cartographers mapped the world from Paris; French navigators calculated longitude from Paris. The Paris Meridian was drawn on French maps for centuries.

The 1884 International Meridian Conference voted to establish Greenwich as the prime meridian. France abstained. The French were not willing to vote for Greenwich, and they were not willing to formally reject it either. For years afterward, French nautical charts used “Paris time” or “Greenwich time” depending on context, with French law not officially adopting Greenwich-based time until 1911.

The French were the last major power to accept the Greenwich standard. The rivalry between the Paris and Greenwich meridians is one of the odder diplomatic footnotes in the history of science.

Today, a brass line in the courtyard of the Paris Observatory still marks the Paris Meridian. Greenwich won, but Paris keeps the line.

The decimal time experiment

During the French Revolution, the new Revolutionary government attempted to decimalize everything, including time. The French Republican Calendar, adopted in 1793, reorganized the year into twelve months of thirty days each, with ten-day weeks and a year beginning in September. Days were divided into ten decimal hours, each decimal hour into 100 decimal minutes, each decimal minute into 100 decimal seconds.

This system made conversions beautifully mathematical and daily life genuinely confusing. Ten-hour clocks were produced. The system was officially in use until 1806, when Napoleon abandoned the Republican Calendar and returned to the Gregorian. Decimal time was used even more briefly, mostly abandoned within a year of introduction because no one wanted to replace all their watches.

France’s experiment with decimal time was a reminder that timekeeping is not purely rational. The accumulated inertia of millions of people’s habits is, in practice, more powerful than a government decree about what the clock should look like.

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