WASHINGTON -- The changes to Washington since the September terrorist attacks were not readily apparent to the tens of thousands of people who came into town Jan. 22 for the annual March for Life.

For the most part, it was business as usual for events surrounding the annual march commemorating the 1973 Supreme Court rulings that legalized abortion.

Busloads of participants still came from around the country. College students from Massachusetts shared floor space with families from Ohio for an overnight vigil in the Basilica of the National Shrine of the Immaculate Conception. Members of the Knights of Columbus waited at corners along Constitution Avenue to guide marchers.

But people who tried to fit in a little sightseeing encountered new security measures and a few closed tourism sites. And those who wanted to lobby their senators first had to find them, since 50 senators were displaced from the Hart Senate Office Building until the afternoon of Jan. 22 because of anthrax contamination and removal.

Even getting to Washington was a bit different this year for some people.

Just across the Potomac River in Virginia, the Arlington Diocese in September instituted restrictions on field trips that includes a prohibition on school-sponsored visits to "highly traveled areas" of Washington, said diocesan schools superintendent Timothy McNiff. That includes the Mall where participants in the March for Life gathered for a rally, he said, so there were no Catholic school-sponsored groups there from the diocese.

Students who would have gone to the march with their schools were encouraged by the diocese to go with their parishes and families instead.

Such restrictions were apparently the exception rather than the norm, however. College, high school and elementary school groups from around the country were everywhere along the march route and they filled Masses and youth rallies at several locations.

Nia Cresham, a teacher at St. Bartholomew's School in Bethesda, Md., said there was no serious discussion about not bringing a group from the school to a youth rally at Constitution Hall. As she waited with a group of middle school students who were going back to their suburban Washington school for afternoon classes, Cresham said she was surprised that security was pretty much the same as in past years.

"I thought there was sure to be more security than what I saw," Cresham said.

A spokesman for the Metropolitan Police Department said there were no plans for more of a police presence than usual this year, even though the March for Life was one of the first big events of its kind since the September attacks. Along the route of the march, city police officers primarily were stationed at intersections for traffic control.

Near Capitol Hill, where Capitol Police have jurisdiction, dozens of officers were in position. Even more conspicuous were huge, round concrete barricades newly installed every few feet along the perimeter of the Capitol.

At the Supreme Court, a phalanx of about 40 Supreme Court Police officers waited on the steps behind metal barricades for potential trouble as thousands of marchers approached. Such a presence is typical for large protests at the court, however, and there were no visible additions to the security related to terrorism.

Just across the street from the court, a small group of Catholics from Pennsylvania was a bit puzzled at how quiet the Hart Senate Office Building was. Carl Wanjek, of Levittown, Pa., and his companions, Eileen Bailey, Mary Jo Marynowski and several teens, said they usually pay visits to members of Congress when they come for the march.

This year, they were practically the only people in the Hart building and they encountered some confusion about where to find the appropriate staffs. They didn't realize the building had been open for less than three hours, reopening that afternoon for the first time since it closed because of anthrax contamination in October.

Wanjek said he'd tried to walk around the White House earlier in the day, only to find that he now had to circle a full city block to do so, because a path along the east side of the building is off limits. He noticed that there are no longer public tours of the president's home. (Tours will resume for school groups only in February.)

It also was much quieter than usual in the Smithsonian museums near the march route. Aside from people who obviously were with the march, only a handful of tourists were scattered through the museums. Two of the three restaurants were closed in the American History Museum, closest to the Washington Monument hillside where a rally preceded the march. The remaining open cafeteria was uncharacteristically not busy for noontime.