For one whole weekend, when people thought Charles River, they thought rowing. Not the river that creates a barrier around Boston's Back Bay. Not a piece of Harvard University's or the Massachusetts Institute of Technology's backyards. Rowing.

An estimated 300,000 spectators flocked to the shores of the 47th Head of the Charles Regatta to watch 1,953 boats compete in a 3.2 mile-long course in 61 events over two days. Nineteen countries and 34 U.S. states were represented in the Head of the Charles, regarded as the world's second largest two-day time-trial boat race. There were competitors ranging from boat clubs to Olympic athletes, senior citizens to teenagers, and also Brandeis' club crew team, which competed in the Club Men's Fours and finished 45th among 53 teams.

"I'm an international and it was a big deal for me," said Sinan Isam '14, who is originally from Turkey and rowed in the prestigious regatta for the first time this weekend. "I don't think that this is something someone does every day."

Brandeis Crew belongs to a local crew league made up mostly of Boston-area schools, routinely competing in the Head of the Charles as well as in other races. Two weeks ago, the Brandeis women came in third at the Quinsigamond Snake Regatta, competing against many varsity rowing teams.

"We're very inclusive. We have a good time, and we don't lose sight of that," said club Co-president Andy Hyde '12. "But it's also important for us to be able to compete with teams who recruit varsity level athletes."

Although Club Men's Fours may not attract Olympic competitors, Brandeis does row the same windy and narrow 3-mile course as the more prestigious racers.

"The course is pretty crazy, lots of crews going at once. It's prone to a lot of crashes," Hyde said.

The risk of a crash was likely on the Brandeis team's mind before the race.

"We were involved in a crash two years ago with an international boat," recalled Hyde. "The way they set themselves up, they couldn't turn properly. They tried to pass under a bridge and tried to make a left turn, but they collided with us. It was technically their fault, but they were pretty upset about what happened. They were supposed to finish the race in the top three."

 If there's a team that understands how a crash can change the outcome of a race, it's Harvard. Last year, the Crimson, neck and neck with Washington University in the Championship Men's Eights, clipped one of their opponent's oars. The infraction cost Harvard first place, finishing two seconds behind the Huskies.

Last Sunday, Harvard faced off against Washington again, this time crossing the finish line in first place without drawing a penalty.

The final piece of the regatta's course consists of navigating through the narrow Eliot Bridge near the Cambridge Boat Club. The bridge blocks headwinds that prevent rowers from going faster in other parts of the course, allowing crews to reach their top speeds. Once Harvard and WashU's boats came into view, the crowd erupted into chants and cheers for the Crimson. Both boats were within inches of one another, the two squads trying to pick up speed in the final stretch.

"It was the perfect race right from the start," said Harvard sophomore Andy Reed. "Our coxswain told us that we made up two lengths. I barely believed him at the time, but after a little while we could hear their screams, feel their oars. It was probably one of the best feelings in the world. Especially going under Eliot, we were both right there. We knew we had them."

Harvard's time of 14 minutes, 17.68 seconds beat out the national U.S. Rowing team by six seconds. It was the first time since 1977 that Harvard won the event.