Museums and galleries across the UK are subject to temporary closures. Those that remain open have safety measures in place, please remember to check venue guidelines before visiting.

Royal Observatory Greenwich

Greater London

50% off entry

Home of Greenwich Mean Time and the Prime Meridian line, the observatory is one of the most important historic scientific sites in the world

Founded by Charles II in 1675, the observatory was built to enable the Astronomer Royal to determine 'the so-much desired longitude of places' – one's exact position east and west while at sea and out of sight of land. The 'quest for longitude' actually took the best part of 60 years and the challenge was opened up to the public in exchange for a £20,000 reward. In the end it was not a famous astronomer who determined longitude, but a little-known Yorkshire carpenter turned clockmaker, John Harrison. All four of his ground-breaking timekeepers are kept in full working order in the Harrison Gallery.

In 1884 the Prime Meridian line was officially decreed as the site of longitude of 0° 0' 0'' and every place on Earth is measured in terms of its distance east or west from this point. The line itself divides the eastern and western hemispheres of the planet. As finding longitude is inseparable from the accurate measurement of time, the Prime Meridian also serves as the co-ordinate base for the calculation of GMT. It means the site is the official starting point for each new day, year and millennium. Before this almost every town in the world kept its own local time.

Permanent collection

The observatory galleries unravel the extraordinary phenomena of time, space and astronomy, through paintings, clocks and other astronomical instruments. There are regular shows at the Peter Harrison Planetarium. Don't miss a chance to explore inside Flamsteed House, designed by Sir Christopher Wren under the commission of the King on the site of Greenwich Castle – previously used as a Guest House and Hunting Lodge by Henry VIII. The house features the Astronomers Royal's apartments and a camera obscura.

Royal Observatory Greenwich

Blackheath Avenue, Greenwich, London, Greater London, SE10 8XJ

020 8858 4422


Opening times

Daily, 10.30am – 4pm (reduced hours due to COVID-19). Pre-booking is necessary.

Please check the website for any planned closures.

COVID-19 update: helping you plan a safe visit

Only visit if you are feeling well and do not have a temperature

Buy your tickets online and pre-book a timeslot

Show your ticket via your phone or printed copy on arrival

Please wear a face covering

Follow the clear one-way systems and safety guidelines on-site

Some interactives will not be available at this time

Use the cleaning stations provided

Be mindful of other visitors

Talk to our staff if you have any questions

Keep your distance to enjoy a safe visit

With a National Art Pass you get

50% off entry
Standard entry price

Price displayed is based on a standard venue entry price. Prices may vary according to ticket type and entry day/time.

Price correct at time of publication.

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