When Railroad Time Went Coast to Coast

On Nov 18, 1883
U.S. and Canadian railways adopt five standardized time zones to replace the hundreds or thousands of local times in communities across the continent. Everyone would soon be operating on "railroad time." Before that day...Thousands of municipalities each worked to their local times. The Chicago Tribune, for instance, showed 27 local times in Michigan, 38 in Wisconsin, 27 in Illinois and 23 in Indiana.

Railroad timetables used about a hundred different standards. A single railroad that traveled east to west would use multiple noons: The Union Pacific, for example, had six different settings in what are today the Central and Mountain zones. The Union Station that served multiple railroads in a big city might have five or six different clocks, one for each railroad in the station, each running on is own time.

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Before 1883 in the United States, most towns and cities set their own local time to noon when the sun was directly overhead. Up until this time, travel was so slow, the difference in the clock from town to town was irrelevant. However, with the emergence of the railroads, hundreds of miles could now be traveled in a single day. It wasn't uncommon for a traveler to set his or her watch by the clock at a train station and travel to the next town only to realize their watch was off. Since, in the United States, the sun reaches "high noon" approximately 1 minute later for approximately every 12 miles traveled towards the West, "the time" in every town was different.
1883

The major railroads in the US agreed to coordinate their clocks and begin operating on "standard time" with four "time zones" established across the nation, centered roughly on the 75th, 90th, 105th, and 120th meridians. On November 18, 1883, telegraph lines transmitted GMT to major cities, where each city was to adjust their official time to their proper zone.

Can you imagine what a mess that would be today? LOL
So convenient was the system of time zones that it thrived entirely on the say-so of the railroads for 35 years. Congress did not enact Standard Time until March 19, 1918, when it also initiated Daylight Saving Time as an efficiency measure during World War I.

from wiki