A young softball player watching as the local middle school’s team practiced at a park in Dilley, Tex., just a few miles from the detention center for migrants.

 

A watermelon sculpture in the main park, commemorating the town’s former position as the unofficial watermelon capital of the country.

 

A member of the Dilley High School football team posing for a portrait at practice one morning.

 

Larry Flores is Dilley’s justice of the peace and also runs the town’s driving school. When the classroom is not in use, he allows the lawyers to use it for meetings. Of the immigrants at the detention center, Mr. Flores said: “All my life I was a migrant worker. I understand what it’s like to suddenly be in a new place.”

 

Women are now being released with ankle monitors. They must be worn at all times, and the bands chafe the skin. Women must plug the unit in to be charged, and some complain that they get burned as the monitor heats up during charging.

 

Soveida Obregon and her sister posing for a portrait in the home they share.

 

Kim Sanders, born in San Antonio, was a hairdresser at Dilley’s only salon. She cut back on her hours there to cut hair at the detention center, where the money was better and more consistent. When asked why, she replied: “Money and my kids. I just want to get some real good paychecks.”

 

A woman and her daughter resting at a house in San Antonio. They had just been released from the family detention center in Dilley, an hour south.

 

A series of oil booms brought a huge influx of men from out of town to work the oilfields. All of the requisite subsidiary services followed.

 

The glow of the stadium lights that dot the 50-acre site of the South Texas Family Residential Center burns throughout the night and can be seen for miles around.

 

Yanira López Lucas cried as she recounted her reasons for leaving her home country.

 

Boys on the Dilley High School varsity football team at a morning practice.

 

A statue and painting of the Virgin of Guadalupe, a Mexican religious icon, in the yard of a Dilley resident.

 

George Cabasos and John Edward Carrillo are oil workers from other towns: George from nearby Pearsall, where his father is the mayor, and John from Corpus Christi.

 

At a Dilley diner, a couple ate breakfast amid a breakfast rush composed of oil workers and employees of CCA, which runs the detention center. The cashier said she might apply for a job at the center in search of a pay raise. Rumors abounded about jobs that could have been created by the center, although many employees were brought in from out of town.

 

Yanira López Lucas spent months at the Mennonite House in San Antonio. After being released last spring from the Karnes detention center about an hour and a half from Dilley, she had become the Mennonite House’s de facto caretaker as she waited for her case to wind its way through the system. With her were her sons, David and Daniel, and her daughter, Melany.

 

Ian Philabaum was the project lead for the legal team on the ground. He helped run training for the volunteers and kept everything in line.

 

A portrait of a family member of Soveida Obregon’s born in Mexico. Ms. Obregon, the mother of the mayor of Dilley, is one of many Dilley residents who can trace their heritage to Mexico within a generation or two.

 

Brian Hoffman, the lead lawyer on the ground working with the detained families last year, after a training session with volunteer lawyers.

 

A woman doing her laundry at the town’s laundromat.

 

Even the town’s cemetery is segregated into a Mexican section and a white section. Here, flowers adorned a grave in the Mexican section.

What happens to a town of 4,000 when the country’s largest detention center for immigrants opens its doors there? That’s the question we at Black Box traveled to Dilley, Tex., last year to try and answer.

Black Box — Christopher Gregory, Natalie Keyssar, Alejandro Torres Viera and me — is a creative cooperative that seeks to find new ways of making and presenting documentary photography. Rather than working alone, we worked as a unit, building off one another’s strengths and together developing the project at each step along the way.

We wanted to tell a story about immigration and detention in the United States not just through the experiences of those detained at Dilley, but also through the lives of the town’s residents. The result is “Welcome to Dilley,” a multiplatform project that takes a deep dive into a place at the heart of the national immigration debate.

The kitchen at the Mennonite House, crowded with volunteers and recently released families.

Late in 2014, the Department of Homeland Security opened the South Texas Family Residential Center, the largest detention center in the country, in Dilley. It was designed as a response to the thousands of women and children — many of whom were seeking asylum from the violence running rampant in their home countries — who had crossed the border en masse the previous summer. The center was made to hold as many as of 2,400 women and children as they worked their way through the immigration system.

Almost immediately, the center became a lightning rod in the nationwide debate about immigration and the legality of family detention, putting Dilley in the news ever since. Following the initial outcry, stories detailed human rights abuses alleged by the detained families. Soon after, the facility became the center of a continuing policy battle about the legality of detaining children. And now it’s the site where families swept up in recent Homeland Security raids wait their turn to be deported.

But before the center opened and the name Dilley became synonymous with the immigration debate, the town was a speck on a map, an hour and a half north of the Mexican border. Who were the people who lived there, and what did they have to say?

Noel Perez, the town’s administrator, called bringing the detention center and its promised 600 jobs a no-brainer. But Mr. Perez remembers a time when, as a young Mexican-American running for local office — one of the first in the region — he lost the election because of tacit racism.

Nowadays, most in Dilley can trace their lineage to Mexico within a generation or two, although that wasn’t always the case. Over the last 50 years, the town has flipped from being a quarter Hispanic and three-quarters white to the inverse.

Soveida Obregon, the 76-year-old mother of Dilley’s current mayor, still talks about the town she knew growing up, divided by railroad tracks: A mud school for Mexicans on one side and a brick one for the Anglo, or white, kids. To this day, the cemetery still has a white section and a Mexican section.

To explore bigger themes in the immigration debate in the United States, we gathered materials that painted a rich portrait of a town, its residents and their unwilling and unwelcome guests, all at the center of one of the most volatile debates in America — who belongs here, and under what circumstances?

Trains going by as the sun set in Dilley. The trains carry freight across the United States-Mexican border.

Many in Dilley, including its Hispanic residents, are unsure what to think of the detention center and the families inside. The jobs didn’t flow as promised. From the perspective of a town where a third of the population lives below the poverty line, the women and children inside detention seem to be treated awfully well. “Why do they get everything, when we work so hard to get the little we have?” wondered folks all over Dilley.

And yet we also spent time with women and children who had been released from the center and found their way to the Mennonite House, an hour north in San Antonio. The house, overseen by the immigration nonprofit Raices, is a refuge where just-released families spend their first hours outside detention in America before heading on to where they would wait for the outcome of their asylum cases, be it Idaho, Arizona or Long Island.

Among its residents was Mirza Dalila, a young mother who fled gang violence in Honduras with her daughter, and another woman and her daughter who had been kidnapped in Veracruz, Mexico, on their journey to the United States. Despite these traumatic experiences, they described detention as a worse ordeal.

“I was desperate to get out of there, because truly, being there was a nightmare,” Ms. Dalila said of her time in Dilley, decrying the prisonlike conditions for women and children who went there seeking asylum.

But reality is never black-and-white. After months of contentious back-and-forth, the families in the detention center are being cycled out in weeks, instead of months, and the future of family detention is in question. Yet women and children continue to surge to the border in record numbers, fleeing unchecked violence in their home countries, while the administration has doubled down on the necessity of family detention.

As the political campaigns rage on, these families and the towns they’re housed in have become talking points in presidential platforms. But for the formerly detained families, and the long-term residents of Dilley, the issue isn’t abstract — it’s a defining facet of their lives.

A group of girls walking to school in early morning in Dilley, holding hands as they crossed paved roads and then ran down a dirt one.

Black Box is a creative agency for visual documentary projects.

Co-published with The New York Times.