Cycling was once the sole domain of Europe but at this year's more than 20 nationalities, from Kazahkstan to South Africa, are represented.
But one nation in recent years, albeit courtesy of one individual, has dominated the race where it matters - in terms of Tour de France wins.
The United States has walked off with the yellow jersey on 10 of the last 21 occasions - seven courtesy of Lance Armstrong and three in the late 80s and early 90s through Greg Lemond.
US RIDERS AT THE TOUR
Lance Armstrong (Discovery)
George Hincapie (Discovery)
Christopher Horner (Saunier)
Bobby Julich (CSC)
Floyd Landis (Phonak)
Levi Leipheimer (G'steiner)
Fred Rodriguez (D-Lotto)
Guido Trenti (Quicktep)
David Zabriskie (CSC)
But the American dominance of 2005 is not solely about Armstrong, with three men from across the Atlantic finishing in the top 10 of the race and nine in total in the peloton.
Armstrong is one of three team leaders at the Tour: his former team-mate Floyd Landis is the joint team boss at Phonak, while another past lieutenant Levi Leipheimer is sharing the honours at Gerolsteiner.
Armstrong sees the upward turn in American cycling as little more than "a phase, but a good phase at that".
He explained: "I remember when I was younger we had the likes of Greg Lemond and Andy Hampsten going for it in the general classification among other riders.
"But as these things happen, there was a slight slump afterwards for whatever reason. Thankfully we seem to be hitting another high now, and there are a few guys realising their potential and going out there."
Landis, who switched to Phonak after three years with Armstrong at US Postal, argues that "slump" and "high" are not necessarily the right words.
"There's always been American riders in the race," Landis told BBC Sport, "well for a long time anyway.
"It just now seems there are more high-quality American riders. And by that I mean riders who are able to push it for the overall win."
The 31-year-old Leipheimer admits to being inspired by Lemond's first win in 1986 and the way in which he stopped Bernard Hinault from winning a sixth Tour in the process.
"That was the first time cycling really got into the American psyche," recalled the Gerolsteiner rider. "I was just a 12-year-old kid.
"The bizarreness of this hideous cycling competition captured people's imaginations even more when he won it back to back in 1989 and 1990. Then it all went nuts with Lance."
Leipheimer hopes the US public will be further inspired by what Armstrong can do this year and by what he and Landis can also do this time and in future Tours.
"It's nice to think what you're doing can inspire kids back home," said Leipheimer, "and I'm sure it does. We've got to keep on doing it to avoid the sort of slump Lance talked of."
The rest of Europe, far too used to American and, in particular Armstrong, domination, will be hopeful another Stateside slump is just around the corner.