<P> The procession sets off two hours before the start and then regroups to precede the riders by an hour and a half . It spreads 20--25 km and takes 40 minutes to pass at between 20 and 60 km / h . Vehicles travel in groups of five . Their position is logged by GPS and from an aircraft and organised on the road by the caravan director--Jean - Pierre Lachaud--an assistant, three motorcyclists, two radio technicians and a breakdown and medical crew . Six motorcyclists from the Garde Républicaine, the élite of the gendarmerie, ride with them . </P> <P> The first three Tours stayed within France . The 1906 race went into Alsace - Lorraine, territory annexed by the German Empire in 1871 after the Franco - Prussian War . Passage was secured through a meeting at Metz between Desgrange's collaborator, Alphonse Steinès, and the German governor . </P> <P> No teams from Italy, Germany or Spain rode in 1939 because of tensions preceding the Second World War (after German assistance to Franco in the Spanish Civil War it was widely expected Spain would join Germany in a European war, though this did not come to pass). Henri Desgrange planned a Tour for 1940, after war had started but before France had been invaded . The route, approved by military authorities, included a route along the Maginot Line . Teams would have been drawn from military units in France, including the British, who would have been organised by a journalist, Bill Mills . Then the Germans invaded and the race was not held again until 1947 (see Tour de France during the Second World War). The first German team after the war was in 1960, although individual Germans had ridden in mixed teams . The Tour has since started in Germany four times: in Cologne in 1965, in Frankfurt in 1980, in West Berlin on the city's 750th anniversary in 1987 and in Düsseldorf in 2017 . Plans to enter East Germany in 1987 were abandoned . </P> <P> Prior to 2013, the Tour de France had visited every region of Metropolitan France except Corsica . Jean - Marie Leblanc, when he was organiser, said the island had never asked for a stage start there . It would be difficult to find accommodation for 4,000 people, he said . The spokesman of the Corsican nationalist party Party of the Corsican Nation, François Alfonsi, said: "The organisers must be afraid of terrorist attacks . If they are really thinking of a possible terrorist action, they are wrong . Our movement, which is nationalist and in favour of self - government, would be delighted if the Tour came to Corsica ." The opening three stages of the 2013 Tour de France were held on Corsica as part of the celebrations for the 100th edition of the race . </P>

When was the tour de france not held