Racing. Revelry. Regattas. Each year, the Head of the Charles ushers in the excitement of major intercollegiate crew races, of fried dough and hot dogs, of autumn foliage lining the celebrated Charles.

But along with the mystique of the regatta arrive thousands of college students, parents, crew enthusiasts and curious observers, all descending on the Harvard campus and in Cambridge.

Harvard Police expects "upwards of 200,000" to attend depending on the weather, said Lieutenant of Special Operations Lawrence J. Murphy.

"They kind of swarm all over Harvard Square...like insects or something," junior Liz Arkush says. "I remember going to Store 24 at one point during the weekend, and there were all these Andover kids going, 'Wow, this is so wild, this is just like the Store 24 at home.'"

"I usually go down to peek at the boats, but it's a pain...we're bombarded with 200,000 of our closest friends," says junior Melissa Bender, '94.

Harvard Police, state Metropolitan police and the Dean of Students office are all acting together this weekend to coordinate security measures.

Yard gates and the main House gates will remain locked throughout a 24-hour period, beginning at 4:00 p.m. today. Access will be restricted to students with Harvard identification cards, each of whom can accompany one guest into the Yard or houses.

In addition, police presence will be increased throughout the campus today and tomorrow, primarily to limit drinking on the Harvard campus and along the Charles River. No kegs will be permitted in the dormitories or houses, Murphy says.

"We've had the same plan in effect for three years, and it seems to work pretty well," Murphy says.

According to College rules, each student may house no more than one guest during the weekend and must first obtain permisson by today, from the appropriate House Office or Freshman Proctor.

Social events must be registered with the Freshman Dean's Office or a House Office in advance, while functions of student organizations or House committees must be registered through the Dean of Students Office.

So far, there are no parties registered by house or student organizations, Assistant Dean of Students Ellen Hapfield Towne says.

"Our assumption is that none will come in [today]," she says. "Because of the heightened security needs, it would be very difficult to get an officer if we did not know well in advance."

"Small private gatherings will be permitted in the usual course of social activity, but anything that escalates into a question of crowd control or an alcohol situation will be carefully monitored," she says. "We strongly want to discourage visitors from finding a party at Harvard and entering the houses."

Many students expressed dissatisfaction with the College's stringent regulations.