Rowers practice on the water yesterday. Hundreds of thousands of competitors and spectators will flock to Cambridge this weekend for the 37th annual Head of the Charles Regatta.

The nation’s biggest rowing event of the fall, the 37th Head of the Charles Regatta, is coming to the Charles River this weekend, bringing with it hundreds of thousands of competitors and spectators.

The community around the Charles is geared up for the two-day rowing extravaganza, as boats are being set up on the river’s banks and crews prepare to compete.

“It’s a fun regatta, aside from just the racing aspect,” said Harvard lightweight co-captain Patrick Todd. “There are just so many fans. Typically, rowing is not that popular of a sport, so it’s amazing that so many people come [to Head of the Charles].”

And precisely because so many people come to Cambridge for Head of the Charles, the University takes extra security precautions all weekend.

Throughout this weekend, guards will be posted at the entrances to Houses and Harvard Yard to ensure that only students with current Harvard identification and their registered guests are allowed into the dorm areas. In addition, kegs and, in some cases, parties of any kind, are banned this weekend.

“Security is always an issue for this weekend anyway just because of the numbers of people who are here,” Radcliffe heavyweight Coach Liz O’Leary said. “This year, sure, there’s a different feel to what’s happening. Times have changed.”

Times may have changed, but

Head of the Charles has not.

The three-mile headrace begins just before the Boston University bridge and ends just after the Eliot bridge.

The contests begin early Saturday afternoon with the Club events and the Master Doubles. The last events of Saturday are two of the most exciting, as the Charles hosts 75 of the best scullers in the world in the Championship Singles. The top three finishers in the headrace will be invited to race again on Sunday in the Charles Schwab Sprint Challenge on a course that begins just after the River Street Bridge and ends at Weeks foot bridge.

On the men’s side, Xeno Mueller, last year’s runner-up in the Challenge, begins at the front of the pack. Mueller, from Switzerland, was the Olympic single sculls silver medalist in 2000 and the champion in 1996. Lightweight Steve Tucker of Medford, a five-time member of U.S. national teams including the 2000 Olympic team and a local rowing community favorite, starts after Mueller. Norway’s Olaf Tufte is third in starting order, as the 2001 FISA World Rowing Champion and the silver medalist in double sculls in the 2000 Olympic games.

For the women, Ekaterina Karsten from Belarus has the first bow number out of the 30 women in the event. Karsten was the Olympic champion in the single scull in both the 1996 and 2000 games. Karsten showed off her stamina in this year’s World Championships where she won bronze medals in both the single and double sculls competitions, events in which both finals took place within an hour and a half of each other. Massachusetts is well represented in this event—Carol Skricki of Norwood, Mass., and Cindy Bishop of Boston, Mass., follow Karsten in the starting order.

The festivities continue on Sunday, with Harvard and Radcliffe rowers competing in several races.

In the men’s Youth Eight, the Harvard freshman boat has earned the first bow number as the Crimson has won the event in each of the past three years. Yale will follow in the starting order. Brown will start 28th in the event, but is expected to be fast, along with river-rival Northeastern.

For the women, St. Catherine’s Rowing Club holds the first start, followed by the Yale novice boat. The Radcliffe novice boat starts seventh, followed immediately by Brown. St. Catherine’s won the event in 1997 and 1998 and the Black and White took first in 1999.