I was in a bad mood when I first met Koshanin, heading home after a work trip that included three cancelled flights. I couldn't get out of Portland International Airport fast enough.

And then I heard the soft tones of a piano being expertly played in the ABC Lobby.

My steps slowed. My shoulders relaxed.

I didn't recognize the music, but it was beautiful, and I stopped to thank its creator. Djordje Vasovic, who performs under the stage name Koshanin, told me he's been a volunteer musician at PDX for five years, and people stop to talk all the time.

"That's telling you as a musician that you're doing something good and you're touching their hearts, because they respond to your music," he said. "It's just beautiful, really."

An airport is the space in between: always part of the journey, never the destination. It's a place where strangers sit in anticipation or anxiety, hope or heartbreak.

An airport isn't a place to relax.

But Portland is trying to change that.

The Port of Portland, which operates the airport, has added art exhibits, a movie theater and other amenities to ease its travelers. It started the music program in 2002.

"9/11 was still pretty fresh on everybody's minds," said Walt Marchbanks, customer relations manager for the airport. "One of our volunteers came to us and said 'Hey, if the Port had a piano, I play the piano and I would love to play for passengers to kind of relieve some of their stress.' "

It started with a single piano, placed below the clock tower before travelers pass through security. Today, the program includes an average of 30 volunteer musicians who perform at four locations throughout the airport. About half the artists are pianists, but you might also hear a guitarist, singer, celloist, violinist or accordionist.

Combined, the musicians give an average of 65 weekly performances, providing some 200 hours of live music to travelers each week.

There's no stage, and that's by design. These performances are meant to be stumbled upon and to feel unexpected.

"We look at music as a way to create ambiance, to create a sense of place, to accentuate the travel experience," Marchbanks said. "Folks come through and there's natural light streaming in and they can smell the food and there's live music and it's a whole experience."

Dan Hergert performs at Portland International Airport on Thursday, July 19, 2018.

Dan Hergert has been playing the piano at the airport for about two years.

"It's the most fun and rewarding thing I've ever done in my life," he said. "Every night is a joy. Over the course of a year, a million people will go by and hear me play. And you think about it, as a musician, to be able to perform for a million people, that's pretty hard."

A million is probably a good estimate. Close to 20 million people total travel through Portland International Airport each year, Marchbanks said.

The musicians aren't paid, but it's a competitive process to perform at PDX. Auditions for open slots are held every few years.

Both Koshanin and Hergert said they've booked gigs from playing at the airport. People leave tips, sure, but they also leave notes, poems and heartfelt thanks.

One night, after Hergert played "What a Wonderful World," an emotional man came up to thank him. He'd just returned from his wife's memorial service, and that had been the first song they'd danced to at their wedding. What were the odds he'd hear that song in the airport terminal?

Koshanin performs at Portland International Airport on Thursday, July 19, 2018. (Samantha Swindler/Staff)

Koshanin moved to Portland in 2010. He was born in Belgrade, which was then part of Yugoslavia. He received a diversity visa in a lottery system that allowed him to immigrate to the U.S. in 1995.

"It was pure luck," he said.

He knew a little English, but sheet music is universal. He got a job at a coffee shop in Cleveland and started touring with a reggae/pop band.

"Just a classic story for any immigrant," he said. "Basically, you just start from the bottom."

Today, he's a full-time musician who composes his own music, influenced by Balkan and Mediterranean rhythms.

"I feel that if I'm playing stuff that people don't know, and if they react to it, that's the pure beauty of music that's touched these people's hearts," Koshanin said. "They don't recognize it, but they recognize, maybe, a fine melody."

Koshanin remembers a woman who was listening to him play and weeping. She left without speaking to him, but sent him an email a few days later.

"She said 'I had such a hard time with my life ... and you just lightened up my whole trip, and your music brought me to tears,' " he said.

-- Samantha Swindler

@editorswindler / 503-294-4031

sswindler@oregonian.com