Meridian Line & Historic Royal Observatory

Suspension of Time Ball

The Time Ball is temporarily not in operation, due to damage from recent weather conditions.

Great Equatorial Telescope closure

On 22, 25–26, 29 August and 1–2 Sept we'll be holding special Venus observing sessions with the Great Equatorial Telescope, which will close at 3.15pm to other visitors. See Venus through the iconic Telescope

The historic Royal Observatory is the home of Greenwich Mean Time (GMT). Enter the Meridian Courtyard to get your essential photo standing on the Meridian Line and explore some of the oldest parts of the site including the Astronomer Royal's house.
Explore & discover

Stand on the historic Prime Meridian of the World and see John Harrison's legendary timekeepers

Who designed the telescope that defined the Prime Meridian?

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So what is longitude anyway and what made it so hard to measure?

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Enjoy a lunch over looking Greenwich Park and pick up a memento of your visit

Find your way

The Meridian Line and historic Royal Observtory is a quick and easy journey from central London, by DLR, rail or boat