Keeping track of time helps us make sense of our world. Read all about the history of timekeeping and the story the Prime Meridian, and discover why Greenwich is known as 'the home of time'.

When do the clocks go forward in 2021?
Marking the start of British Summer Time, the clocks 'spring forward' in March, meaning we'll lose an hour's sleep
Visit the home of time
Visit the home of Greenwich Mean Time and discover how time-keeping, astronomy, global exploration and world communications are all intricately linked.
What is Greenwich Mean Time (GMT) - and why does it matter?
How did local clock time in Greenwich change the world?
20 May 2016
100 years of Daylight Saving
On the centenary of Daylight Saving in Britain, Curator of Horology, Rory McEvoy looks back at its history.
Sir George Biddell Airy
Astronomer George Biddell Airy designed the legendary Airy Transit Circle telescope which defined the Prime Meridian at the Royal Observatory Greenwich.
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.
What is the Prime Meridian and why is it in Greenwich?
Why was Greenwich chosen as the home of the Prime Meridian and Greenwich Mean Time, and what do those terms mean?
Meridian astronomy
Meridian astronomy is the meticulous surveying of the stars so that positions and movements of stars can be known accurately.
Airy's Transit Circle and the dawn of the Universal Day
The story of Astronomer Royal George Biddell Airy and the remarkable Airy Transit Circle telescope he designed at the Royal Observatory Greenwich.