The Olympic Torch - straight from Olympia, Greece - today begins the first leg of its 82-day journey from the United Nations Building at 42nd Street and First Avenue to the Los Angeles Coliseum, where it will officially open the 23rd Olympic Games.
Along the way, the torch will be borne by more than 4,200 runners striding through 33 states across 15,000 kilometers (8,700 miles), renewing the tradition of a marathon relay that dates back to 776 BC in Olympia.
The relay, called the Youth Legacy Kilometers, is sanctioned by the Los Angeles Olympic Organizing Committee (LAOOC) to help raise $12 million for youth organizations. Legacy torchbearers - each of whom will run one kilometer - find sponsors to contribute the $3,000 cost of running in the relay.
But the Grecian torch - which arrived by plane in New York City yesterday afternoon - almost never left Olympia. Officials in Olympia, the original site of the games, charged that the American relay fund raiser is ''too commercial.''
To protest the LAOOC fund raiser, Olympia last week canceled its own ceremony - a ritual during which the flame is lit in honor of the ancient Greek god, Zeus. And city leaders threatened not to allow the LAOOC to use the torch.
But the cancellation was reversed after Greek President Constantine Caramanlis intervened. The ceremony in Olympia was held yesterday under tight security measures, to ensure there would be no disturbances.
With the torch now in America, the marathon is expected to get under way this morning. Grandchildren of two of America's most famous stars of the Olympic Games - Gina Hemphill of Chicago, granddaughter of Jesse Owens and William Thorpe Jr. of Texas, grandson of Jim Thorpe - will jointly carry the torch the first kilometer of the race.
Olympic fans will readily recall the two grandfathers.
Jesse Owens was the black sprinter who won four Olympic gold medals in 1936 in Berlin as Adolph Hitler watched his ''Ayrian superman'' theories disintegrate. The German chancellor did not shake hands with Owens after his triumphs. Owens broke two Olympic records in the sprints and tied a third in the long jump. He also ran the anchor leg for the winning US 400-meter relay team which set a world record.
Jim Thorpe was the superb Indian athlete who won gold medals in the pentathlon and decathlon in 1912, but forfeited them for the indiscretion of accepting pay for playing summer baseball. His medals have been restored, but his grandson, calling the return ''too late,'' is running in tribute to his grandfather. Thorpe's marks in the decathlon (10 track and field events) are the standard for this event today in competition worldwide.
In addition to the runners with Youth Legacy Kilometers, a special cadre of more than 200 trained runners will carry the flame for 11,000 unsubsidized kilometers. The runners were recruited by American Telephone & Telegraph (AT&T), which is sponsoring the torch relay. Their job? Make up time lost by legacy runners.
This torch relay will be unlike any other in history: Computer technology, rolling modern kitchen vans, and updated radar weather forecasts will help keep the torchbearers on a precise schedule.
From New York, runners will bear north toward Boston, America's Cradle of Liberty. Among the relayers will be legacy runner Cenk Mesta, a teen-ager who wants to be an Olympian when he grows older, and James Kinsellagh of AT&T, a cadre man.
''My son enlisted me to help him raise $3,000 (for the legacy fund),'' says Ali Mesta of Boston. ''He was so enthusiastic that he collected the needed funds quickly. Now he is awaiting his turn with the torch.''
Mr. Kinsellagh, who is legally blind, says: ''I volunteered because this was my once-in-a-lifetime opportunity to be part of the Olympic spirit of achieving excellence.'' He ran the Boston Marathon in 3:02 as ''part of my training.''
The Olympic Games began in 776 BC and continued uninterrupted for 1,000 years. Then Emperor Theodosius I of Rome cancelled the Olympics in the fourth century AD.
The Olympic Games were revived as the First Olympiad in Athens in 1896. Since then, the Olympics have been scheduled every four years - although the 1916, 1940, and 1944 games were not held because of World War I and World War II.
The Grecian torch was not used in the modern games until 1936, when the Olympia torch was relayed from Athens to Berlin. This is the third Olympics to be held in the United States - in St. Louis in 1904 and in Los Angeles in 1932. (The Coliseum was built for the 1932 games, and the sponsors devised their own torch relay.)
Mack Moore of Wichita, Kan., a teacher who raised his own $3,000, calls his run ''a thrill of a lifetime for me, for my wife and two-year-old son, and for the 35 people who contributed to my kilometer.''
And others will run, too, for youth - Abel R. Kiviat, 91, of Lakehurst, N.J., the oldest living American track and field Olympian from the 1912 Olympics; Billy Brown, a 1936 Olympian; handicapped Amy Haas, 8, of Stilwell, Kan.; celebrities such as Arnold Palmer and O.J. Simpson with Boys Club members in Pittsburgh and Los Angeles; and a Hells Angels runner of Ventura, Calif.
Youth Legacy Kilometers funds will be donated to the Boys Clubs and Girls Clubs of America, family YMCAs, and Special Olympics, say LAOOC spokesmen.