NEW YORK — When fashion designers offer up their odes to America, they tend to nibble around the country’s edges. They love the shimmering skyline of Manhattan and the attitude of Brooklyn hipsters. They are entranced by California  — the glamour of Hollywood and the beauty of the sweeping Pacific coastline. And every now and again, they will dabble in Texas cowboys or Miami decadence. But they rarely venture into the heartland.

Designers love to riff on the uniform of the wealthy. Or they elevate the sturdy, humble clothes of the poor. Fashion is more comfortable with extremes.

Tuesday night, Raf Simons’s Calvin Klein 205W39NYC collection reflected the vast geographic region that holds the edges together. He celebrated the philosophical middle. The presentation, he said in his show notes, was about freedom.

His collection, titled “Landscapes,” was filled with handmade sweaters, firefighter coats, billowing work shirts, Loony Tune-emblazoned sweaters, prairie dresses and a host of details that call to mind marching bands, quilts and small-town America.

Simons’s beautifully expressed vision was unveiled at the American Stock Exchange building in the Financial District. It had been wholly transformed with the help of artist Sterling Ruby into an expressionist rendering of a farm landscape covered in snow. The ankle-deep fluff, however, wasn’t styrofoam peanuts or confetti. It was popcorn. Surely an entire silo’s worth of corn kernels had been popped and poured into the building so that clouds of popcorn dust billowed up as guests trekked to their seats.

The room was also set with wooden benches, stools with bright red tractor seats, and skeletal 19th century barns with walls plastered with plastered with artwork by Andy Warhol. The setting gave the entire collection a surreal, popcorn-movie quality — everything was more vivid, more lyrical.

Simons showed both menswear and womenswear on his runway, and the two collections were in constant, natural dialogue. The women were afforded the same chunky-knit sweaters, the same oversized coats, the same head-swaddling knit hats. There were broadly tailored wool plaid coats lined in shearling. Silver space-blanket jackets were backed with quilting. Oversize fireman-style coats gave a nod to these first responders’ wardrobe that felt more like appreciation than mimicry.

But while the prairie dresses look romantic when flowing out from beneath a chunky sweater or an oversized coat, the idea of a full Laura Ingalls Wilder fashion moment during one’s morning commute may have been Simons’s sole miscalculation. His patchwork dresses, however, were captivating.

Simons is reinventing the way in which Calvin Klein is defined in the popular imagination. He’s moving it away from a minimalist, sensual aesthetic towards one that is rooted in Americana, the visual arts and a kind of melancholy optimism. His youth are not raging against the system; they are considering precisely what the system means and how best to change it.

Simons is also establishing his own vocabulary. And for fall, he references the cadet pants and marching-band shirts that appeared one year ago in his first collection for the brand. As he moves from season to season, Simons isn’t dismissing what came before; he’s building on it. And for customers, that’s reassuring. It means the designer has faith that what he is doing now will still be relevant in a year or longer.

As Simons’s models stomped through the field of popcorn, they did so to evocative music from the 1960s — “The Sound of Silence,” “California Dreaming,” sweet-toned songs of longing, discontent and upheaval. But songs that also reflected a time of forward-progression in race relations, technology, civic engagement.

Simons continues to explore the America beyond the surface gloss, beyond the Chamber of Commerce pitch and far, far beyond the edges.