Ticketed Essential Information Location Royal Observatory Price Included with entry to the Royal Observatory Members go free. Not a member? Join now Book tickets Plan your visit See the historic Royal Observatory Flamsteed House is the original Royal Observatory building at Greenwich. King Charles II instructed Wren, who was also an astronomer, to design the building in 1675 and it was completed the following year. While you're here, you can: Watch the Time Ball drop - On top of Flamsteed House is one of the world’s earliest public time signals, the bright red Time Ball, which has been in operation since 1833. See it drop at 1pm every day. Enjoy the panorama from the Camera Obscura - Using a lens and rotating mirror, the camera obscura projects a close-up real-time moving panorama of Greenwich and the Thames, the National Maritime Museum, the Queen's House and the Royal Naval College. Explore the Octagon Room - The beautiful Octagon Room was designed to observe celestial events including eclipses, comets and planetary movements. Today it houses a selection of timepieces and astronomical instruments. Get to grips with Longitude in the Time Galleries - Learn the story of Longitude, marvel at the Harrison clocks and see where sea navigation is at now. Visit the Astronomers Royal Apartments - Take a fascinating glimpse into the apartments where the Astronomers Royal and their families lived and worked in our Observatory Life display. Buy a ticket to Flamsteed House and also get access to the Astronomy and Time Galleries, and the Meridian Courtyard (age 4 and under go free). The historic site also includes the Prime Meridian of the World and the UK's largest refracting telescope. Octagon Room The positioning of Flamsteed House meant that the original purpose of the Royal Observatory could not be fulfilled from the Octagon Room. With big windows, the room was perfect for watching the sky, but not ideal for positional observations, because none of the walls were aligned with a meridian. Most important positional observations were actually made in a small outhouse in the gardens. Find out more about the Octagon Room Astronomers Royal apartments The role of Astronomer Royal was created by Charles II in 1675, when he appointed John Flamsteed to draw up a map of the heavens with enough accuracy to be reliable for navigation. Since Flamsteed there have been nine Astronomers Royal, including Edmond Halley and Nevil Maskelyne, each of whom have contributed to the world’s understanding of the stars, time and space. Time and Longitude At sea, navigation is a matter of life and death. Out of sight of land, how can you tell where you are? Time and Longitude tells the story of the quest to find longitude at sea in the age before satellite navigation, and showcases Harrison's celebrated sea clocks. Find out more about the Time and Longitude gallery Time and Greenwich This gallery looks at the historical need to develop increasingly accurate timekeeping see amazing objects including the actual GPS receiver used by Sir Robin Knox-Johnston on his record-breaking round-the-world voyage of 1994. Visit us Royal Observatory Plan your visit Top things to do You might also enjoy What is Greenwich Mean Time (GMT) - and why does it matter? How did local clock time in Greenwich change the world? Longitude found - the story of Harrison's Clocks Who was John Harrison, and how did his clocks help to solve the problem of finding longitude at sea? Stand on the Prime Meridian Line Stand on the historic Prime Meridian of the World at the home of Greenwich Mean Time (GMT) The Shepherd Gate Clock Make time to find the clock at the heart of Britain's time system The Great Equatorial Telescope at the Royal Observatory Stand beneath the magnificent onion dome and marvel at one of the largest refracting telescopes in the world Altazimuth Pavilion See the beautiful Altazimuth Pavilion, home of the Annie Maunder Astrographic Telescope Airy Transit Circle Telescope The Prime Meridian was defined at the Royal Observatory Greenwich by the legendary Airy Transit Circle telescope Royal Museums Greenwich Close Choose your tickets Royal Observatory Walk the Prime Meridian line See the best view in London Guaranteed entry time Audio guide included Planetarium shows not included Adult £18 Child £9 BOOK NOW Royal Museums Greenwich Day Pass Save 25% with combo ticket Cutty Sark Royal Observatory Guaranteed entry time Planetarium shows not included Adult £27 Child £13.50 BOOK NOW Member tickets Free and fast-track Museums entry Priority booking Access using your membership card Membership card number required BOOK NOW Become a Member Unlimited entry all year Royal Observatory Cutty Sark Planetarium Shows Special exhibitions Direct Debit One-off Individual: £50 Individual: £60 Family: from £60 Family: from £70 JOIN TODAY