Greenwich is a charming and historic area of London that is best known for lending its name to the time by which the British set their clocks - Greenwich Mean Time. It is also home to a number of touristic attractions such as the Cutty Sark and the Maritime Museum.Greenwich meridian, imaginary line used to indicate 0° longitude that passes through Greenwich, a borough of London, and terminates at the North and South poles. ... The Greenwich meridian also serves as the basis for the world's standard time zone system.Visit Cutty Sark the world’s only surviving extreme clipper. ... Cutty Sark represents the pinnacle of clipper ship design and was one of the fastest ships of its day.