When you’re a tour guide in Washington, D.C., you never know what you’ll encounter. Any given day, the nation’s capital plays host to all kinds of groups, protests, parades, and commemorations.

One Sunday a couple of weeks ago, I was guiding a Japanese tour through the city when we encountered a pretty unusual sight in front of the Capitol building. A row of about 25 policemen on horses, lined up across the National Mall.

The officers were from all different regions of the country, wearing distinct state uniforms and riding different breeds of horses.

It made a great sight, especially with the statue of Civil War General and President Ulysses S. Grant astride his own horse looming just behind them.

Turns out, it was National Police Week, and that Sunday was Peace Officers Memorial Day.

President Kennedy first designated May 15 as the date to commemorate the nation’s law enforcement officers back in 1962.

On this May 15, we had stumbled into the National Peace Officers’ Memorial Service, a ceremony started in the capital in 1982 to honor those police men and women who have made the ultimate sacrifice. Tens of thousands of police officers and supporters gather in D.C. for this and other events throughout Police Week.

We paused to listen as the national anthem was sung on the Capitol steps – a special treat for visiting foreigners who had just arrived the previous day – and then watched as the officers slowly processed their horses off the Mall.

It seemed like good timing that we were able to see the mounted parade, not realizing we would have ample time to see it up close again later – we got caught in a horse traffic jam on Independence Avenue on our way to the Jefferson Memorial.

In Washington, you don’t have to wait until May 15 to honor the country’s police men and women – you can do it throughout the year by visiting the National Law Enforcement Officers Memorial.

It’s somewhat hidden in plain sight in a courtyard at the metro entrance for Judiciary Square. The area is home to D.C.’s many courthouses, making a nice juxtaposition of law and order.

This Sunday, I had the opportunity to add the memorial to a tour itinerary for the first time with a European group of law enforcement officers. We walked past the symbolic lion statues guarding the entrance and followed along the memorial’s curved walls, reading some of the names inscribed there.

The memorial was built in 1991, but it has the names of all the known officers killed in the line of duty since 1791. There are nearly 19,000 names – sadly, new ones are added each year during National Police Week.

Next time you’re visiting one of Judiciary Square’s courthouses, it’s worth stopping by the National Law Enforcement Officers Memorial to pay your respects.

Let’s just hope that you’re in the neighborhood on jury duty, and not as a defendant.