In the fall of 2014, two Afghan police officers, Mohammed Naweed Samimi and Mohammed Yasin Ataye, travelled to America on temporary visas. For five weeks, along with other law-enforcement officers from Afghanistan, they attended lectures on intelligence-gathering techniques at a Drug Enforcement Administration facility in Virginia. One Saturday, the trainees took buses into Washington, D.C., for a day of sightseeing. That evening, they all returned to the buses—except for Samimi and Ataye.

They had contacted an Afghan family in suburban Virginia, who picked them up in Washington and drove them to their house. From there, Samimi and Ataye took a bus to Buffalo, New York. Their destination was a safe house known as Vive, at 50 Wyoming Avenue, on the east side of the city. At Vive, a staff composed largely of volunteers welcomes asylum seekers from around the world. A dozen or so people show up each day, looking for advice, protection, and a place to sleep.

Vive occupies a former schoolhouse next door to an abandoned neo-Gothic church with boarded-up windows. More than a quarter of the nearby properties are vacant “zombie homes,” and the area contains some of the cheapest real estate in America. Vive residents rarely venture into the neighborhood. A staff member told me, “Agents from the Border Patrol circle the building all the time.” So far, the schoolhouse has not yet been subjected to a raid, which would require a warrant.

In theory, people who come to Vive could have stayed in their home countries and applied for a visa through the U.S. State Department’s lottery system. But in 2015, out of more than nine million visa applications, fewer than fifty thousand were granted. For people in urgent situations abroad, there is another option: they can simply show up in a safe country and request asylum. Those with money fly directly to the U.S. on tourist visas and, upon arriving, request protection. Poorer migrants stow away on boats, hop on freight trains, and cross deserts. After making their way out of Africa or Asia, they often head to Latin America and then travel overland to the U.S. border. Some hire human traffickers to smuggle them. Many show up at Vive almost penniless.

Of the people who arrived at the schoolhouse last year, roughly ten per cent came from the seven countries included in the Trump Administration’s proposed travel ban. Most arrivals do not intend to stay in the U.S. In recent years, it has become increasingly difficult to win asylum in America, and since 2011 the number of pending asylum requests has grown tenfold; applicants often wait years for an answer, and in the end more than half are rejected. But there’s another option, just four miles due west of Vive’s schoolhouse, across the Niagara River: Canada.

In December, 2015, when a plane filled with Syrian refugees landed in Toronto, Canada’s Prime Minister, Justin Trudeau, greeted them at the airport, handing out winter coats. President Donald Trump, meanwhile, has pledged to purge the U.S. of “bad hombres.” Trudeau has been echoing the openness of his father, Prime Minister Pierre Trudeau, who, in 1980, went on television and welcomed Cambodian refugees to Canada. As of 2015, Canada granted asylum to sixty-two per cent of applicants. It also offers far better social services than the U.S. does, including access to education, temporary health services, emergency housing, and legal aid. But to make a claim for asylum in Canada you first have to get there, and the easiest route is across the U.S. border.

Vive has become the penultimate stop on a modern variant of the Underground Railroad. Vive was founded, in 1984, by nuns, though most of the staff is now secular. More than a hundred thousand refugees, from about a hundred countries, have passed through. Nearly all of them continued on to Canada. Niagara Falls, twenty miles away, was once a major hub on the original Underground Railroad. During the nineteenth century, many fugitive slaves came through the area on the way to sneaking into Canada and winning their freedom. Harriet Tubman led groups across a suspension bridge that spanned the gorge, and some slaves allegedly braved the rapids of the Niagara River, swimming to the other side.

The two Afghan cops, Samimi and Ataye, also had their eyes on Canada. But, shortly after they arrived at Vive, two D.E.A. agents appeared at 50 Wyoming Avenue. They showed photographs of the two runaways to residents who stepped outside. Word spread that the D.E.A. was in the parking lot.

Inside the schoolhouse, one of Vive’s staff managers, a young man named Jake Steinmetz, asked Samimi and Ataye some questions. They explained who they were, and said that if they returned to Afghanistan they would be ordered to patrol poppy fields; given their known connections to the U.S. government, they would be in extreme danger.

“I really didn’t know what to do,” Steinmetz said. On principle, Vive does not turn away people seeking sanctuary, unless they physically threaten other residents. When I asked one staff member if Vive admitted “fugitives,” she replied that all asylum seekers were running from someone, or some place. After Steinmetz spoke with Samimi and Ataye, he went home; the next morning, he returned to find that the two men had left for Canada.

U.S. officials apprehended them before they made it to the border. They soon went back to Afghanistan. (I recently contacted Samimi, who said, “I hope to go again to Canada, because my life here is so hard and dangerous.”) Steinmetz and the other staff members at Vive barely had time to absorb the Afghans’ drama; by the end of the day, a new group of asylum seekers had arrived on their doorstep.

The battered red brick façade of the Vive schoolhouse does not look welcoming, but its doors never close, and a cafeteria in the basement serves three free meals a day. There is a computer room and a nurse’s office; upstairs, dormitories can billet a hundred and twenty residents. The accommodations are clean, if rudimentary: creaky wooden floors, clanking radiators, leaky bathrooms, and steel-framed beds. “Bedbugs love wooden beds, so we got rid of them,” a volunteer named Tom Lynch, who is a retired Spanish teacher, told me. The heart of the building is the rec room, where residents gather to play pool.

Arriving migrants check in, as if Vive were a motel. They are asked to provide I.D.—a birth certificate, a passport—and to pay for their accommodations. The official cost is a hundred dollars per person per week, but the staff does not eject people if they can’t pay. Nor are residents forced to answer questions. “At no point do we ask them what their story is—if they share it, that is completely up to them,” one staff member explained.

Vive is a small organization that is funded through grants and donations. It is operated by a skeleton crew of six full-time employees, including two program managers, a receptionist, and three security guards. There are also four part-time employees, including a social worker, and two dozen volunteers. A local lawyer offers counsel to residents. When I first visited Vive, the reception area was full. A volunteer warned new arrivals, “This is a very dangerous neighborhood. Do not ever go out alone. And never go outside at night!” This directive, combined with fear of the U.S. Border Patrol, led some residents to describe Vive to me as a kind of jail.