Greenwich Mean Time

Discover why Greenwich is known as 'the home of time'

Drone photograph of the Royal Observatory lit up at night

History of the Royal Observatory

Find out more about the founding of the Royal Observatory, and how Greenwich came to be known as the 'Home of Time'
An image of a gold watch with a large face with roman numeral numbers on it, and two watch hands

Time before Greenwich Mean Time: the confusing case of the traveller's watch

Before time became standardised, different areas of the country all kept their own 'local time'. This gold traveller's watch with two minute hands shows how tricky that could be
Mid 1900s photograph of Flamsteed House at the Royal Observatory

The Greenwich Time Lady: Ruth Belville

Discover the story behind the media sensation Ruth Belville, who brought the correct time from the Royal Observatory to London for almost 50 years.
Black and white Shepherd Gate Clock on a brick wall.

What is Greenwich Mean Time (GMT) - and why does it matter?

How did local clock time in Greenwich change the world?

The Greenwich Time Ball and one time for all

How do you know that your watch, clock or phone is telling exactly the right time? At one time, the only way was to look to the roof of the Observatory.
A crowd looking at the Shepherd Gate Clock on a brick wall.

British Summer Time (BST) and Daylight Saving - understanding UK time changes

Why does UK time change, and when was British Summer Time first introduced? Explore the history of BST and daylight saving
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