Until the 19th century, every city had its own local time determined by the sun's position. Noon was when the sun was highest – and that differed in every city. How did we get to the global time zone system?

The Chaos Before Time Zones

Before 1880, the US alone had over 300 different local times. Each city set clocks by the local solar noon. This wasn't a problem when traveling by foot or horse – differences were minimal.

The Railway Changes Everything

With the rise of railways, the time chaos became a real problem. Timetables were nearly impossible to create, and accidents occurred due to conflicting times. On November 18, 1883, US railway companies introduced four standard time zones – the "Day of Two Noons."

Sandford Fleming and World Time Zones

Canadian engineer Sir Sandford Fleming proposed a global system of 24 time zones in 1879, each 15 degrees of longitude wide. In 1884, the International Meridian Conference in Washington established the Prime Meridian through Greenwich.

Key Milestones

Year	Event
1847	Britain adopts Greenwich Mean Time (GMT) for railways
1883	US railways introduce 4 standard time zones
1884	International Meridian Conference establishes Greenwich as Prime Meridian
1972	UTC replaces GMT as official world standard
2011	Samoa switches sides of the International Date Line

Curiosities

China has only one time zone (UTC+8), though it spans 5 geographic zones
India uses UTC+5:30 – a half-hour offset
Nepal uses UTC+5:45 – the only quarter-hour offset in the world
France has the most time zones worldwide (12) due to overseas territories