Halloween was celebrated in a quiet fashion last night in Georgetown, where police officers in blue uniforms seemed to outnumber revelers in vampire and witch costumes.

Police estimated the crowd at 30,000, about half the number that showed up last year. And in a departure from years past, almost no one appeared to be drinking on the streets -- with good reason. District police were out in force, guarding street corners, mingling with the people on the sidewalks and telling dawdlers to keep moving.

For the first time in several years, officials kept streets in the area open to motor traffic, instead of shutting them so that celebrators could gather en masse. Police also set up pylons at the entrances to side streets to prevent non-residents from parking there.

In addition, curbs were blocked off with yellow crime-scene tape to prevent people from crossing streets except at intersections. Those who tried to defy the rule were intercepted quickly by officers and escorted back to the sidewalk.

By early this morning, police had made 19 arrests in Georgetown, most for disorderly conduct.

It also was quiet in the Virginia and Maryland suburbs, where police reported no serious problems related to the evening's festivities.

Typical was the situation in Old Town Alexandria, where police Lt. Ken Howard said the crowd was "not any different from a crowd on a warm Saturday night, except a lot of people are dressed funny."

The evening wasn't entirely without incident in the District. At 17th and Q streets NW about 11 p.m., an annual foot race by men dressed as women drew a large crowd that spilled into 17th Street and blocked traffic. Police, saying that the gathering was a fire hazard, cleared the street, prompting complaints from some of the revelers.

Several other large groups gathered in the Dupont Cirle area throughout the evening, but no problems were reported.

D.C. Police Chief Isaac Fulwood Jr., who announced last month that officers would be out in force to discourage people from gathering in Georgetown, said he was pleased with the situation there last night.

"I'm happy . . . . They are not in the street," Fulwood said, adding that the police strategy was to keep traffic moving and to "not lose control of the streets." Such control has its price, though: The police effort will cost the city $284,000 in extra pay, Fulwood said.

For residents of the upscale Georgetown area, the absence of what had become an annual bout of craziness was a welcome change.

"It's actually so quiet tonight that I thought they'd canceled Halloween," said Gavin Wilson, who lives in the 1200 block of M Street NW. "If this could happen every Friday or Saturday night, it would be idyllic."

The largest Halloween gathering in Georgetown was in 1987, when an estimated 150,000 revelers crammed onto the streets and sidewalks. After appeals by officials for people to stay away, the crowds fell to 75,000 in 1988 and 60,000 last year, police said.

However, last year's celebration turned ugly when a brawl broke out in the early morning hours and three men were stabbed, one of them fatally.

Officials took several steps to keep the crowds manageable last night. They sent letters to bar owners urging them not to promote Halloween and to local university officials urging them to discourage students from converging on Georgetown.

The city's tactics appeared to be a success. But not everyone was happy about it; some revelers said the police presence was so pervasive that it put a damper on the fun.

"Why are all the police here? I think they're kind of intimidating," said Jeanne Fillbrandt, who came from Southern California with her husband, Jim, because they had heard that the gatherings were fun. "I think we could have had a better time in Santa Barbara."

Staff writers Stephen Buckley and Carlos Sanchez contributed to this report.