Royal Observatory & Prime Meridian: Early Access + Guided Tour

Founded in 1675, the Royal Observatory is Britain’s oldest scientific institution. Get a chance to see it before the crowds arrive. You'll stand on the Prime Meridian and step into the birthplace of modern astronomy. Your knowledgeable guide will explain the history of Greenwich Mean Time (GMT) and the search for longitude. See the Octagon Room, designed by Sir Christopher Wren, and enjoy a tour that brings to life the stories of how the Prime Meridian was established in Greenwich.

The Royal Observatory Greenwich, founded in 1675 by King Charles II, is known as the home of British astronomy. At the home of space and time, you'll learn all about the Greenwich Mean Time (GMT), and how the search for a way to measure longitude led it to be the Prime Meridian of the world back in 1884. Situated on a hill in Greenwich Park in southeast London, it overlooks the River Thames to the north and is surrounded by a picturesque view, including that of the Queen's House.