From Ancient Olympia to the opening ceremony, the Olympic flame has played a big part in the Games for nearly a century.

Flames burn in the Olympic cauldron after being lit during the opening ceremony of the 2016 Summer Olympics in Rio de Janeiro, Brazil, Saturday, Aug. 6, 2016.

Over the years, the flame has played an increasingly larger role at the opening ceremony, with the identity of the final torch bearer – often former Olympic greats from the host country – being the topic of feverish discussion.

Jorge Alberto Oliveira Gomes lights the Olympic cauldron during the opening ceremony of the Rio de Janeiro 2016 Summer Olympics, Brazil, Saturday, Aug. 6, 2016.

The Olympic cauldron is lit during the Opening Ceremony of the London 2012 Summer Olympics, London, the U.K., Saturday, July 28, 2012.

Li Ning lights the Olympic Torch during the opening ceremony for the Beijing 2008 Olympics, Beijing, China, Friday, Aug. 8, 2008.

The Olympic cauldron rises in this multiple exposure photo (L) after Nikolas Kaklamanakis (R) lights it during the Opening Ceremony of the 2004 Olympic Games, Athens, Friday, Aug. 13, 2004.

The photo on the left is a single frame time exposure interrupted at six intervals while the Olympic cauldron rises after being lit.

Australian champion runner Cathy Freeman stands under the Olympic torch after lighting the flame at the opening ceremony for the 2000 Summer Olympics, Sydney, Australia, Sept. 15, 2000.

Boxing legend Muhammed Ali lights the Olympic flame, as American swimmer Janet Evans looks on during the 1996 Atlanta Summer Olympic Games opening ceremony, Atlanta, the U.S., July 19, 1996.

An arrow carrying the Olympic flame leaves the bow of Antonio Rebollo to light the Olympic Torch and open the XXV Olympic Games in Barcelona, Spain, Saturday, July 25, 1992.

Pigeons fly around as the Olympic torch is lit during the opening ceremony in Seoul, South Korea, Sept. 17, 1988.

Gymnastics athlete Sandra Henderson (L) and track and field athlete Stéphane Préfontaine lighting the Olympic Flame during the Montreal 1976 Olympics, Montreal, Canada, July 17, 1976.

Runner Guenther Zahn stands near the Olympic flame he lit above the Olympic Stadium on Aug. 26, 1972, during the opening ceremony of the Munich Summer Olympic Games, Munich, Germany.

The Olympic Torch burns during the opening day ceremony in Mexico City, Mexico, Oct. 12, 1968.

Rafer Johnson, 1960 gold medalist for the decathlon, lights the Olympic Torch during the Opening Ceremony of the 23rd Olympiad in Los Angeles, the U.S., 1984.

Soviet athlete Sergei Belov runs past the Olympic team from Afghanistan with the Olympic flame during the opening ceremony of the 1980 Moscow Summer Olympic Games, Moscow, the former USSR, Saturday, July 20, 1980.

A number of teams boycotted the ceremony to protest the Soviet intervention in Afghanistan.

Italian student Giancarlo Peris holds the torch after lighting the Olympic flame in the tall tripod brazier on the perimeter of the Olympic Stadium in Rome, Italy, Aug. 25, 1960, at the formal opening of the XVII modern Olympiad.

Runner Paavo Nurmi of Finland lights the Olympic flame from the Olympic torch, during the opening ceremony, Helsinki, Finland, July 19, 1952.

Australian athlete Ron Clark, (bottom L), plunges the Olympic torch into a bronze bowl to light the Olympic flame, which burnt throughout the XVI Olympic Games, Melbourne, Australia, Nov. 22, 1956.

British athlete John Mark runs with the Olympic flame (L) and lights the cauldron (R) during the opening ceremony of the XIV Olympiad, Wembley Stadium, London, the U.K., July 29, 1948.

The Olympic torch in Lustgarten, Berlin, is lit on Aug. 1, 1936, where it was guarded by members of the Hitler Youth until it was brought to the Olympic stadium for the opening of the games in the afternoon. The torch relay was not always a fixture of the modern Olympics that began in 1896. The relay tradition began with Adolph Hitler's 1936 Olympics in Berlin, Germany.

Doves are released during the opening ceremony for the Tenth Olympiad in Los Angeles, the U.S., July 30, 1932. The athletes of various countries stand on the field.