Participants in the 2013 Police Unity Tour. (Courtesy PoliceUnityTour37.com)

Tens of thousands of law enforcement officers from across the country are set to converge on Washington in the coming days for "Police Week" to honor their fallen colleagues.

And for former police officer Bobby Egbert, the commitment made by officers who swore an oath to protect the public at any cost is a visceral one.

"There have been many [situations] every police officer gets into where all of a sudden it strikes them, 'Oh my God, I don't want to do this. I want to get out of here,'" Egbert said. "But you raised your hand, you took an oath, you have to do it. It's that simple."

The commemoration of their sacrifice begins unofficially on Friday, hundreds of miles from the nation's capital, when more than 1,600 current and former law enforcement officers jump on bicycles and start pedaling their way to Washington as part of the Police Unity Tour.

And for Egbert, a former Port Authority of New York and New Jersey police officer who founded a New York chapter of the tour, the commemoration begins at the site of one of the nation's most enduring symbols of sacrifice: the World Trade Center.

Egbert described it all as "extremely personal." And through the bicycle tour, he's doing what he can to help raise funds for the National Law Enforcement Officers Memorial in Washington, so the more than 20,000 law enforcement officers who were killed in the line of duty and whose names are now inscribed on the memorial's walls are never forgotten.

For Egbert, the commitment it takes to bike from New York City - or elsewhere in the country - to Washington honors the commitment made by law enforcement to protect and serve the public.

"When I came on a scene [as an officer], I used to look in people's eyes, and I could see through the panic in their eyes a certain level of comfort because I'm on the scene now. But they never understood that I'm just as frightened - if not more - than they are," Egbert recalled. "But I have to now go beyond that and do what I swore I would do."

His chapter of the Police Unity Tour is known as Chapter 37 - named for the 37 Port Authority officers who lost their lives in the World Trade Center towers on Sept. 11, 2001.

On Friday morning, like on one morning every May since the 9/11 attacks, Chapter 37 will meet at the World Trade Center. Before jumping on their bicycles, they will hold a "short, solemn" ceremony, reading the names of the 72 federal, state and local law enforcement officers who died on Sept. 11, 2001, and the names of officers in the state of New York who were killed in the past year, according to Egbert.

In May 2002, Egbert was joined by only five fellow officers. This year, he'll be joined by about 150 others - the most his chapter is allowed.

As soon as Friday morning's ceremony is over, the officers will head straight for the Holland Tunnel.

"These are all grown men and women police officers, but as soon as they hit the tunnel, they're like little kids - they start hooting and hollering to hear the echoing and all that," Egbert said.

That first day, the group will ride only about 40 miles to Somerset, N.J., stopping in certain cities along to way to pay tribute to officers killed in each of them.

Over the next two days, Chapter 37 will join other chapters from the New York and New Jersey area, hundreds of officers pedaling nearly 10 hours a day on their way south.

"You get a lot of people pissed off. … We screw up traffic over three days from New York City to D.C.," Egbert said with a bit of a laugh.

On Monday morning, the New York-area chapters and others based in Virginia, Florida and even California will converge on Robert F. Kennedy Memorial Stadium in Washington, linking up for the final ride toward the National Law Enforcement Officers Memorial a few miles away.

Thousands of people will be lining the streets of Washington to cheer the officers on toward the memorial. But the reality of the memorial is not lost in all the cheer.

"When you actually go into that memorial … there are thousands of people there, but it's really a solitary moment," Egbert noted. "You walk through that memorial, and the experience is sometimes overwhelming. It's not unusual to see police officers with tears in their eyes [or] kneeling down next to a name that they see on the wall that they know. It's a very moving experience."

The Police Unity Tour began in May 1997 with 18 officers on bicycles, organized by Patrick Montuore, now chief of the Florham Park Police Department in New Jersey.

Last year's tour raised more than $1.7 million for the law enforcement officer's memorial, and this year's event is expected to bring in more than $2 million, according to Egbert, who is also a spokesman for the Port Authority Police Benevolent Association, the union that represents Port Authority police officers.

In recent years, the money has helped fund a restoration project at the memorial, according to the Unity Tour's website.

In 2013, 100 officers were killed in the line of duty.