But don't be fooled, it's carnage on some nights.
Race marshals and bank party supporters for each boat ride along the tow path on bicycles at breakneck speeds shouting encouragement and using complicated whistle signals to tell their crews how close they are to a bump.
Boats career into the river bank, hit each other and sink. Sometimes crew members are ejected at speed from the boats or lose a tooth when they lose control of the oar, known as "catching a crab."
The two most dangerous spots in the boat are the coxswain (the person who sits in the stern and steers the boat) and the crewmember rowing in the bow.
Coxswain Fiona Knights said sometimes crews coming up behind will try to hit the coxswain to force them to concede.
"I've had a blade hit me in the lower back, scrape all the way up to my ear and rip out my earring," she said.
Andrew Watson, who comes from a celebrated Cambridge rowing family and at 42 years old is still competing at elite events like the Henley Royal Regatta against top rowers half his age, said most things about the bumps have remained the same since he first rowed it 27 years ago.
"When we used to row then, if you could taste the blood in your mouth, then you knew you were doing it," he said. "Now they're wearing heart monitors and using sports science."
Local rowing legend Paul Knights, who has been head of the river five times and boatman for Queens' and Magdalene College since 1984, said the only difference between the Town Bumps and the university version was the full day's work first.
The 51-year-old former British indoor rowing champion and another veteran of Henley said the unique beauty of bumps racing instead of the usual side by side racing at regattas has brought him back every year since 1972.
"It's the thrill of the chase," he said.
"You're the hunter being hunted."
