Each summer, the bicycle race takes over the entire country, with nearly 200 cyclists hurtling to the finish line. They ride for 23 days, a brutal affair for even the most prepared athletes. More than 20 teams have to make it through the 21 stages of the race.
But the continent is in the midst of a record heat wave that surely only makes it more difficult to bike thousands of miles in what's essentially a sweltering oven.
Some cyclists are strapping on ice vests before the start of each race, while others are consuming atypical amounts of water just to stay standing; the risks of heatstroke and other related injuries are high, and the asphalt may as well be the bottom of a frying pan.
Though high temperatures have been sweeping Europe for the past few weeks, the ferocity of the heat blindsided many riders.
"Yesterday on paper was a flat sprint stage to ease us back into the third week, and then, bang, a 39-degree average" or 102.2 degrees Fahrenheit, Britain's Alex Dowsett said, according to VeloNews. "So it's just always something you have to deal with."
The temperatures started at 86 Fahrenheit on Wednesday morning and tracked upward through the day, peaking at 98 degrees.
The heat is so bad, some riders asked for something to be done.
"I don't think this is healthy. Maybe the organization has to do something when the temperatures are so extremely high," the Netherlands' Steven Kruijswijk told VeloNews.
Salvation may come in the next few days as the riders cross the mountainous terrain of the Alps. Temperatures are likely to be cooler there, and the competitors may even get a few scattered showers.
But as the heat creeps into the mountains, it will probably still be 10 degrees hotter than normal. Add the rocky, steep terrain they'll be cycling through, and the the elevated temperatures may nudge toward unbearable.