( CNN ) -- Thousands of years after the first athletes competed at the ancient stadium in Greece , a high priestess swathed in white lit a flame from the sun to mark the start of a new Olympiad on Thursday . The Olympics are as much about tradition and legacy as they are sporting events , with none so vivid as the lighting of the torch which will now wind its way from Olympia to the Games in London . The solemn ceremony , held in the ruins of the 2,600-year-old Temple of Hera , saw actors in ancient Greek costume use a mirror to harness the sun 's rays and light the Olympic torch . It marks the start of the flame 's week-long journey to Britain , where it will begin an 8,000-mile ( 12,875-kilometer ) route across the country before entering at the new stadium in east London . Taking center stage in the lighting ceremony was Greek actress Ino Menegaki as the traditional high priestess . Among the dignitaries present were International Olympic Committee president Jacques Rogge and London organizing committee chairman Sebastian Coe . The first relay runner to take the flame was Greece 's Liverpool-born open water swimming champion Spyros Gianniotis . He then passed it to 19-year-old British boxer Alexander Loukos , who grew up in east London where the Olympic Stadium is now situated , but whose father hails from Greece . Making its way to Britain , the flame will first take in Greek archaeological sites including the Acropolis and Olympic Stadium in Athens , site of the first modern Games in 1896 . Arriving on May 19 at Land 's End in the far southwest of England , it will then wind its way through 1,019 communities , carried by 8,000 torch-bearers . The final leg will run from Hampton Court Palace , the former home of King Henry VIII , before arriving at the opening ceremony on July 27 . The flame will burn until the Games end on August 12 -- a tradition that was revived at the 1936 Berlin Olympics .
Actors dressed in ancient Greek costumes light the Olympic torch at original stadium . Solemn lighting marks the start of torch 's year - long journey to Britain . Torch will be carried by 8,000 relay runners and run 500 miles across Europe . First light is Greece 's champion swimmer Spyros Gianniotis .