Le Tour de France is a bicycle race that covers approximately 3,600 kilometers (2,200 mi) throughout France and bordering countries. The race lasts three weeks and attracts cyclists from around the world. The race is broken into day-long segments, called stages. Individual times to finish each stage are totaled to determine the overall winner at the end of the race. The rider with the lowest aggregate time at the end of each day wears a yellow jersey. The course changes every year, but it has always finished in Paris. Since 1975, the climax of the final stage has been along the Champs-Élysées. The Tour de France is the best known and most prestigious of cycling three “Grand Tours”. The other two Grand Tours are the Giro d’Italia (Italy) held every May and the Vuelta a España (Spain) held every August–September. The 2010 Tour de France is currently in progress, from 3 July till 25 July 2010, from Rotterdam to Paris.
source