Seven-time champion Lance Armstrong made his return to the Tour de France on Saturday after completing the opening stage time trial.
The 37-year-old American clocked a time of 20min 12.36sec for the race against the clock. It gave him the provisional lead with a 30sec advantage on Belgian Maxime Monfort, although most of the favourites for the overall victory had yet to start.
Armstrong, who rides for the same Astana team as yellow jersey favourite Alberto Contador, started 18th from the field of 180 riders.
They will all race towards the end at one-and-a-half minute intervals. Defending yellow jersey champion Carlos Sastre is last to start.