Seeing the Tour de France in person usually involves waiting around, sometimes for hours, to catch a glimpse of riders that often lasts for seconds. Now, some people are going through all that trouble to turn their backs on the race.
With front-facing cameras now standard equipment on smartphones, an increasing number of spectators lining the Tour's route are taking selfies with the riders as the background, adding a danger to a sport already fraught with them.
Since the Tour began Saturday, several riders, including Tejay van Garderen, the American leader of the BMC team, have been knocked off their bikes by self-portrait enthusiasts standing on the course.
While no one has yet been seriously injured, the development angers and frightens many riders. On a crowd-packed climb in Britain, Ramunas Navardauskas, a Lithuanian with Garmin-Sharp, vented his frustration by knocking down a smartphone a spectator was holding in his face.
The Tour de France is a rare major sporting event in which uncontrolled crowds can come in such proximity to the athletes. Scenes of riders carefully navigating through hordes on the roads are common. Previously, though, the danger usually came from people who had their eyes on the race.
"More and more people definitely have their backs to the race," said Alex Howes, an American teammate of Navardauskas's. "I think things in the camera are closer than they appear. They need to put a disclaimer on the iPhone or something."
Asked how common brushes with selfie takers have become, Howes added: "How many riders did we start with, 198? I think 198 guys have had some near misses in the Tour this year."
Careless photography has long been a safety issue for the Tour. In 1994, a policeman who was supposed to be protecting the riders stepped in front a group of sprinters making their way to the finish line at 72 kilometres an hour or so to grab a picture. Two of the riders were forced to abandon the race, and a third was injured.
But Juan Antonio Flecha, a Spanish rider who retired at the end of last season, said that the arrival of camera phones escalated the problem. Teams and sponsors are somewhat to blame, he added, by encouraging people to post selfies on social media in the hope of winning prizes.
"Now they've got a problem, and I don't expect them to stop it," Flecha said. "When you visit the Tour de France now, you can share it with the rest of the world, which is bringing more people to see the race."
The problem, which van Garderen called a "dangerous mix of vanity and stupidity," was particularly acute with the huge crowds that lined the road during the three days the Tour spent in Britain. Bethany Scott and her boyfriend, Sam Davison-Webb, were among them when the Tour began in Leeds, their hometown.
Scott acknowledged that she had not "taken note" of the Tour de France until it arrived in Leeds, nor did she know what to anticipate.
"It was a lot bigger than I expected; it was a lot quicker than I expected," she said. "It was just crazy with all the people."
Scott said Davison-Webb suggested immediately before the riders appeared that they turn around and snap a self-portrait with his phone. She then posted the result on Twitter, Facebook and Instagram.
While she had not received any negative comments about the picture, Scott was aware that it was becoming a concern.
"I think there has been a lot of exaggeration," she said of critics of Tour selfies, adding that she thought it was important to capture photos of oneself at a major event.
But she had some safety advice. Scott said that many of the people near her, whether they were taking photos or not, were too close.
"I was thinking, 'Step back and let them get on with it,'" she said.
Christian Meier, a Canadian on the Australian Orica GreenEdge team, said selfie takers often were unaware of how far into the road they were standing. Compounding the problem, the width of the pack shifts constantly as riders fight for advantageous positions, and its speed varies.
"People will move out of your way because they're facing you, but the one guy with his back to the road is still standing there because he's so focused on his tablet or his phone," he said. "I'm not so sure it's worth that for a photo."
Meier said he had already "shoulder checked" one photographer during the Tour.
"Luckily I just sort of saw it and braced for it, and it didn't really cause a big incident," he said. "But I think it might have given him a sore shoulder."
Like many, Jonathan Vaughters, the manager of Garmin-Sharp and a former rider, said that the potential for much more serious injury to either spectators or riders was high.
"These guys are inches from the side of the road, and they're going 40 miles an hour," he said as several spectators snapped pictures with their phones. "Think about it. Would you lean out and take a picture in open traffic on a highway? I know it's a beautiful sport, and I know photographically it's incredible. But you're putting your life in your hands and you're putting the rider's life in your hands when you do that."
The Tour continues to increase the number of points along routes that are lined with crowd barriers, but putting barriers along hundreds of miles each day is implausible, and there is no way to prevent spectators from leaning over them to snap pictures.
Howes and Meier said that much of the problem seemed to stem from people who knew little about bike races. The Tour organization has an online campaign urging spectators to behave, and cars with loudspeakers do the same along the race route.
But something else worries riders more than people taking self-portraits along the route.
"A lot of times you see people with a baby in their arms out in the peloton," Meier said. "The danger level of that is extreme."