Make your way to the Royal Observatory Greenwich which is located on a hill in Greenwich Royal Park. As you do, you will enjoy dramatic views of London across Greenwich Royal Park, the City of London and the River Thames. Once inside, you can pick up a complementary audio guide. There are 7 languages available. Your visit will begin in the Meridian Courtyard where you will stand astride the Prime Meridian Line, with one foot in the east and the other in the west at the home of Greenwich Mean Time (GMT).   The tour will take you through Flamsteed House where you will walk in the footsteps of the Astronomers Royal. Visit the Octagon Room which was designed by Sir Christopher Wren and is one of the best preserved Wren interiors in London. See Harrison’s clocks, the inventions that changed the world. Discover the Shepherd Gate Clock, mounted outside, which was the first clock to show Greenwich Mean Time to the public. Learn about the discoveries of great scientists and inventors based at or associated with the Royal Observatory, including Harrison, Newton, Halley, Bradley, Maunder, Harrison, Airy, Einstein. The bright red Time Ball on top of Flamsteed House is one of the world’s earliest public time signals and was first used in 1833 and still operates today. Don’t miss the Great Equatorial Telescope, located in the huge iconic onion dome, which gave astronomers new views of the universe over 100 years ago.  Located in the UNESCO World Heritage Site of Maritime Greenwich, the National Maritime Museum and the Queen’s House are both located within a short walking distance from the Observatory and are free to visit. Cutty Sark, the world’s sole-surviving tea clipper is now an award-winning museum and visitor experience and is a must-see when visiting Greenwich.