You well might know this house - that is, if you've ever strolled south of Rittenhouse Square. With its marble facade, it's unique among its brick neighbors on a flag-bedecked block where lights twinkle in the cherry trees and ginkgos.

"Königsallee," says a sign in the window. That means "King's Way," the boulevard along the canal in Düsseldorf, Germany, another handsome, tree-lined street that must be dear to someone here.

That someone is Marc Redemann, 39, a German native who lives now on Addison Street with his Philadelphia bride of three years, Adrienne Frangakis, 37. She, too, is fond of Düsseldorf, where she once followed her heart. But it was Philadelphia where they fell in love and where they married, but where they never intended to live.

She escorts a visitor to their living room, where one senses cultures blending. Sleek furnishings feel distinctly European, but some touches bespeak funky Philly.

On the fireplace mantel is a replica of the LOVE sculpture, emblematic of a city and a sentiment. In a wedding photo at Logan Square, the lovers smile blithely as a mischievous boy balances on the fountain's brim.

They have prominently displayed a collage of local scenes, bearing these words: "Found each other in Philadelphia." In the master bedroom are a painting of the Düsseldorf skyline and a "stefanothiki" display of their wedding crowns, made in Greece. And in each room are Redemann's photos: Paris, Bali, Germany, Philadelphia, and Egypt, where they honeymooned.

"We speak German, mostly, to each other here," Frangakis says. "It helps Marc feel more at home."

They met in 2003, as he was on a one-year software-consulting assignment with IDS Scheer. Frangakis had come to Philadelphia to attend the University of Pennsylvania, traveled as a math and French teacher, and returned. She now works in export sales for Reynolds Services.

Frangakis' neighbor was throwing a Halloween party. The neighbor happened to be Redemann's supervisor. Adrienne went as a flamenco dancer, Marc as a chicken; romance ensued. They smile wistfully at the memory of those days, of intimate evenings on the roof deck of his Old City apartment building.

And then he was gone, back to Düsseldorf. She eventually moved there, and in 2007, on a trip to the Canary Islands, he proposed. They didn't intend to leave Germany, but one thing was certain: They would marry in the city where it all began.

To prepare for the wedding, Adrienne returned to Philadelphia and stayed with a friend on Addison Street. A for-sale sign went up on the adjoining house. She texted Marc about it, as a joke, she says. "The next thing I knew, he was on a plane to Philly."

Three days later, they put in an offer, and Marc requested a U.S. transfer - "there was just something about the house." They moved in six months later.

After three years, she muses, "We must have been crazy to buy a house that needed so much work." She learned something about her new husband: He is quite handy, and he welcomed the challenge. "Working on the house," she says, "is his relaxation."

Marc is technically inclined, too, as evidenced by the elaborate speaker system throughout the house, and by a slide show he created showing all they'd done. He used a computer schematic for the house redesign.

But he's also acquainted with a hammer and saw. So is his father, a retired physician. When Marc's parents visited, he and his father built a balcony of Brazilian hardwood and, atop the roof, a deck. Adrienne points to their "cuddle corner," then sweeps her arm across the skyline. This is their favorite spot.

Adrienne felt the house's potential when she first stepped into the living room, though the fireplace was cinderblock, which they tiled. They refinished the parquet floor and installed wide windows. Their goal was "an open-space feel for a Philly rowhome," Marc says. "Every centimeter is utilized."

The "wow" moment came when Adrienne, an accomplished cook, saw the kitchen. It was a dream. The former owner had remodeled it into a stainless-steel expanse of high-end Wolf appliances with counter space aplenty and room to display her Rosenthal china.

They did much of the work before moving in, but they have far from stopped. Cinderblock got brick facing. Baths were transformed with new tile and modern stylings to replace the blue fixtures. Drop ceilings and old paneling came down. The house, built pre-Civil War, had last undergone major renovations in the '60s and '70s.

That's when the marble facade went up. "We thought it gave the house character," Marc says. They refurbished it, though some neighbors would have preferred it restored to brick conformity.

Their decorating emphasizes red, her favorite color, and brown, his. "The decor has a European feel," Adrienne says, "but we wanted homey, too, which the brown tones help to produce. I don't want the sleek and modern to be sterile. So we're a good team."

"It was somehow meant to be," adds Marc, perhaps referring to their house, in Philadelphia, or to their life together, here or anywhere.

No doubt both.

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