The Pentagon Memorial to the victims of the Sept. 11 attacks is a contemplative spot. But it is not a quiet one.

Highways surrounding the Pentagon rumble with traffic. Every few minutes, departures from nearby Ronald Reagan Washington National Airport fly low and loud across the sky.

Every time the planes fly by, a visitor's imagination can't help but contemplate the force and fury with which American Airlines Flight 77 crashed into the Pentagon's west wall, killing 184 people.

"Everyone mentions the planes," said Lisa Dolan, who heads up a team of nearly 50 volunteer docents at the memorial, and whose husband -- Navy Capt. Robert Dolan -- was killed in the attack. "It's an uncomfortable feeling."

The Pentagon was the first of the three attack sites to open an official memorial. It was dedicated Sept. 11, 2008, and is open 24 hours a day, 365 days a year.

It sits at the exact spot where the attack occurred. It is not a tourist-friendly location. Mass transit riders who take the Metrorail have a bit of a hike from the Pentagon train station to the memorial. Driving on the notoriously convoluted network of roads in that section of Arlington County can be confusing for natives, much less tourists. But there was never any serious consideration of putting the memorial any place else.

"It was really important to the families to have it here, where the event happened," Dolan said.

Once visitors arrive, the park's layout is designed to emphasize both the individual loss of each victim and the scope and scale of the 184 deaths.

The main feature is 184 cantilevered benches, each sitting atop a small reflecting pool, and each one dedicated to one of the 184 people killed. The benches are arranged by year of birth, reminding visitors that the attacks claimed lives both young and old, from 3-year-old Dana Falkenberg to 71-year-old- retired Navy Capt. John D. Yamnicky.

No one keeps an exact count of how many people visit the memorial, but Emily Cassell, director of Arlington County's convention and visitor services, said the estimates run between 225,000 and 250,000 annually. That's far less than the estimated 4 million visitors a year that go to nearby Arlington National Cemetery, but Cassell said awareness of the Pentagon Memorial is growing.

The docents are frequently there on weekends and sometimes on weekdays as well. Many are, like Dolan, family members of people who lost their lives in the attack.

"The visitors are really and truly pulled in" when they speak to a docent with a personal connection to Sept. 11, Dolan said. "I've been out here, hugged by people I've never even met before."

Visitors sometimes treat the grounds almost reverentially, leery of sitting on the benches for fear that it's inappropriate. But Dolan said the park is designed to be interactive -- kids sometimes slide down the sloped benches, and that's OK.

Dolan recalled seeing the grandson of one of the victims at the park, sliding down the bench dedicated to his grandmother.

"He had the biggest smile on his face. For him it was like being at the park with his grandmother," Dolan said.

If you go:

Pentagon Memorial: 1 Rotary Road on the Pentagon Reservation in Arlington, Va. ( and The memorial is always open, barring an elevated threat at the Pentagon or certain special commemorative events. Free admission. Visitors are encouraged to use the Pentagon stop on the yellow and blue lines of the region's Metrorail system. Those driving to the memorial can park for a fee at the Fashion Centre mall at Pentagon City. The Pentagon parking lots are generally off limits to the public, though the Hayes Street lot is usually available to visitors on nights and weekends.