(CNN) -- Every May, thousands of tennis fans descend on Stade Roland Garros in Paris to watch their heroes battle for French Open glory.
The setting for the clay-court grand slam is the epitome of style and French elegance, with its location in the chic 16th arrondissement a major part of the attraction.
Named after a famous French aviator, Roland Garros first staged the tournament in 1928 -- but when World War II intervened it served a darker, non-sporting purpose.
Paris-based research center Memorial de la Shoah owns archive material that confirms Roland Garros was used by the French government as a prison camp or "centre de rassemblement" for political dissidents and foreign nationals.
For a 10-month period from September 1939 until June 1940, several hundred prisoners -- possibly more because no accurate records have been kept -- were kept under close guard in the grounds and bleachers of the stadium.
The center, which is dedicated to chronicling the persecution of Jews during World War II, provided CNN with written accounts from people imprisoned there plus evidence from Nazi officers.
One letter, which can be seen in the picture gallery above, was sent to a welfare group set up to protect Jewish immigrants by five internees complaining about the conditions in which they were confined.
"We the undersigned Jews who left Central Europe in the wake of anti-Semitic persecution and being held at Roland Garros stadium, have the honor to speak to the Committee for the rights of Jews to ask him to kindly send a delegate on site that could safeguard our interests," it read.
Those who signed the letter were aged 18-51, including a medical student, engineer, mechanic, furrier and pianist.
This evidence corroborates that of Jewish author Arthur Koestler, who was held at Roland Garros and later wrote about his experiences.
Born in Hungary, Koestler was a member of the German Communist Party in the 1930s and, as a foreign national living in Paris, was rounded up and taken to Roland Garros.
The prisoners were poorly treated according to Koestler, who chronicled his plight in his autobiographical book "Scum of the Earth" -- which was published in 1941 after he fled to Britain.
"At Roland Garros, we called ourselves the cave dwellers, about 600 of us who lived beneath the stairways of the stadium," he wrote.
"We slept on straw -- wet straw, because the place leaked. We were so crammed in, we felt like sardines ... It smells of filth and excrement, and only slits of light can find their way inside.
"Few of us knew anything about tennis, but when we were allowed to take our walk in the stadium, we could see the names (Jean) Borotra and (Jacques) Brugnon on the scoreboard."
Koestler was sent to the notorious Le Vernet camp before volunteering to join the French Foreign Legion, later deserting and finding his way to England where he spent the rest of his life.
The pair he referred to were members of the "Four Musketeers" who dominated pre-war French tennis.
Borotra went on to become the General Commissioner for Sports in the Vichy government before himself being arrested by the Gestapo in 1942 and deported to a prison camp in Germany from which he later escaped.
The Shoah archives also include a chain of correspondence from SS captain Dr. Heinz Rothke -- who headed Jewish Affairs for the Nazis in Paris in February 1942 -- to SS major Rolf Gunther, a senior member of Adolf Eichmann's staff in Berlin.
Gunther asked if the tennis stadium is still being used to hold prisoners, and whether any Jews were being held there. Rothke's reply said that Roland Garros had not been used for purposes of internment since June 1940.
The French tennis federation (FFT) has not included details of the internment of prisoners in its official history of Roland Garros. When contacted by CNN, it declined to comment.
However, the FFT has previously acknowledged that the stadium was used to hold political prisoners, though it denies any Jews or Nazis were ever confined there.
"They were German, Austrian and Italian," its cultural director Jean Christophe Piffaut told the Jerusalem Post in 2004.
"France at this time was terrified to be spied on by the enemies. As soon as the French authorities had verified the reality of the activities of the people that were in this curious camp, they let them free."
The Shoah center said allegations by news organizations including the BBC that Roland Garros had an even more sinister use as an internment camp for Jews were untrue.
It has been reported that Jews were held there before being deported to death camps in Germany during the rule of the Vichy government in Nazi-occupied Paris.
According to Karen Taeb, the Shoah center's chief archivist, there is "no evidence" to support these claims.
Yet it is known that other sports stadiums were utilized.
Cycling's Velodrome d'Hiver (Winter Velodrome), like Roland Garros, acted as a temporary internment camp from 1939-40 for women prisoners.
But in 1942, on July 16-17, it was used for the infamous "Rafle du Vel d'Hiv" which saw more than 12,000 Jews rounded up with 8,000 taken to the cycling track ahead of deportation to concentration camps.
Shimon Samuels, the director of international relations at the Paris branch of the Simon Wiesenthal Center, said sports stadiums were often used for such purposes.
"It is a blight on the honor of sports," he told CNN.