Why do we have time zones?

In the zone
If you've ever travelled to another country,
you may have had to change the time on
your watch or phone when you got there.
Or you may have watched a show or a
football game live on TV, and noticed it
was dark there while it was still daylight
where you were. Have you ever wondered
why that is?
Every country in the world is located within
a time zone. Let's find out what they are
and why we have them in the first place.
Brain Freeze
Because the Earth spins on its axis,
different parts of our planet receive light
from the Sun, while others are in darkness.
Watch Brain Freeze's Doctor Knowles and
Professor McCork explain more.
Doctor Knowles, Professor McCork
and Ms Hucklebuck investigate time
zones and find out why the Earth
spins on its axis.
Earth is divided by imaginary vertical lines
known as meridians, which run from the
North to the South Pole. Time zones are
loosely based on these lines. The prime
meridian from which all others are
measured is located in Greenwich, London.
As you travel east from Greenwich, each
time zone you pass through is another
hour ahead of the current time in
Greenwich. If you were to travel west, each
time zone would be an hour earlier. Sounds
easy? Hmmm - read on to see if it really
is!
Where in the world?
Click on the image below and then on the
labels to read some curious facts about
time zones in different parts of the world.
Beware: time can get pretty confusing!
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You now know everything about the
different time zones in the world, but did
you know there was a time when even
cities in the UK were on different times?
Read on to find out more.
The train now arriving...
Boats and planes have made the
world a smaller place.
In 1830, when the world's first passenger
railway opened at Liverpool Road in
Manchester, a sundial was installed.
As a train travelled around the country,
each station it stopped at would have a
local time determined by a sundial. This
made keeping the railway running to an
accurate timetable very difficult. By the
1840s the railway companies were
campaigning for a single universal time
zone to be used across the country.
In 1847, a universal time as set by the
Royal Observatory in Greenwich, London,
was adopted by railway companies across
Great Britain, and then across the country.
As the world became more connected
thanks to travel and trade, the benefits of
time zones became apparent. In 1884
Greenwich Mean Time (GMT) was adopted
as a standard time across the world. All
ships travelling from country to country
could carry accurate clocks known as
chronometers, which would be set to the
time in London. Adjustments could then be
made to account for local time when the
ships arrived. Many large countries like
China and India would have many different
time zones.
The Manchester sundial
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Where next?
Fleur East
investigates time
Why does time
fly when you're
having fun?
What are day
and night? Test your map
knowledge
In the zone 1
Brain Freeze 2
Where in the world? 3
The train now arriving... 4
Quiz time: Do you know your time
zones?
5
Where next? 6
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Quiz time: Do you
know your time
zones?
Working out what the time is in cities
around the world can be harder than it
sounds. Using your terrific time skills,
can you tackle these tricky time zone
teasers?
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