Greenwich Time

Half marathon notice

Visitor notice: On Sunday 4 March Cutty Sark and the museum car park will be closed for the Vitality Big Half Marathon. All other museums will be open as normal and DLR and rail links will be running. Find out about road closures

Discover some of the timekeepers that have helped shape the history of the Royal Observatory.

Sometimes a clock is just a clock but ever so often a timekeeping device becomes the beating heart of a powerful empire or the key to unlocking one of the great mysteries of navigation.

Shepherd gate clock

See this slave clock connected to the Shepherd master clock yourself to the left of the gate at the Royal Observatory.

Image of the Dolphin dial at the Royal Observatory

How can a dolphin tell the time to the nearest minute?

Angle clock by Tompion

Imagine if you created a whole new type of clock, how would it work? Find Flamsteed's brilliant (but doomed) attempt to make a perfect astronomers' clock.

William Hardy transit clock

Clock this special time-keeper designed to keep astronomers on time when star hunting.