I want to go to Fort McHenry, was what I said that afternoon, over beers, on my last day in America.

It seemed fitting. There we were, wandering around Baltimore, getting ready to deploy, and there was this perfectly fascinating National Monument, where our National Anthem was inspired and written within a measly 25 minutes.

If we’re going, we have to go now, I said, trying to be indifferent, trying not to totally lose my nerd shit over this seemly perfect opportunity. We’d have an hour, give or take, to explore if we left then, was what I told them, they who had already agreed to go with me. I was being unnecessarily persuasive, I knew, but couldn’t seem to stop.

We jumped right into viewing the film when we got there, learning about the fort’s five-pointed star design, how it was built in 1798 and used continuously from then through WWI and then in WWII by the Coast Guard.

It was built to protect the Port of Baltimore, which it did. In 1814, Fort McHenry withstood 25 continuous hours of bombardment and still managed to bar the British from entering the Baltimore Harbor.

We learned that Francis Scott Key watched the bombardment from a nearby ship. Seeing the emergence of an oversized American flag on the morning after the bombardment, Key wrote the poem “Defence of Fort M’Henry,” later renamed as The Star-Spangled Banner,” and adopted as our national anthem.

At the end of the film the screen rose, the Anthem started to play and there in the distance was the flag.

There have been decisive moments of patriotism over the course of my 32 years and that moment, standing there, watching the flag, all of what was to come weighing on my mind, is one of them.

We walked to the fort. Examined the cannons, some prison cells used during the Civil War, and were called to the flag pole. We learned that, in 1948, President Truman signed a Presidential Proclamation declaring that a flag would always fly over Fort McHenry. In the mornings and at night, they switch the flag, flying a historic flag over the site during visiting hours and  the 50-star flag we know today when the park is closed. Being there at the closing of the park, we were able to watch and participate in the flag exchange.

First, the 50-star flag goes up, then the historic flag comes down. There’s never a moment when there isn’t a flag flying there, but there are a few minutes, those in between minutes, when there are two flags flying over the fort.

I took pictures as the boys helped catch the oversized historic flag and then helped fold it with the rest of the crowd.

I never know what I’m going to experience when I visit a National Park. I continue to do it, continue to visit because it continues to be special and I am continuously rewarded with each new visit, each new park. They always remind me of the beauty, history and magnificence of our nation, of the reasons I’m proud, of the reasons I serve.

This visit was treasure. It could not have been timed better, could not have taken place on another day of my life when it meant as much to be as it did that day. It was the perfect transition, the perfect reminder of why.