A Syrian refugee waits to be transferred to the Moria registration center, after arriving at the port of Mytilene on the Greek island of Lesbos, following a rescue operation by the Greek Coast Guard at open sea on March 21. (Alkis Konstantinidis/Reuters)

On the isle of Lesbos, there are now two facilities to house the migrants who risked their lives crossing the sea. The Syrian refugees call them the good camp and the bad camp.

The good camp is airy and open, and migrants are getting ready to sail to the Greek mainland, where there is still a chance they may reach their dream destinations in Germany, Sweden or France.

In the bad camp, there is razor wire and a locked gate, and the police are preparing the asylum seekers for a forced ferry ride back to where they came from.

The two transit centers show in stark relief the past and future for migrants clamoring to reach Europe.

It is here that Europe will answer the big questions: Will Greece really send people fleeing war and chaos in Syria and Iraq back to Turkey, by force if necessary?

The Europeans say they will — starting Monday.

Greek officials said the first ferries are scheduled to take the first migrants back to Turkey next week. They hope the move stems the tide of newcomers.

Humanitarian organizations, along with the U.N. refugee agency, warn that the returns are being rushed, that Greece could be overwhelmed. The asylum seekers will not get a full hearing, they say. The aid organizations worry that traumatized people may balk at being herded onto boats and sent to uncertain conditions in Turkey.

“The risk is that they will do everything very, very quickly and create an assembly line for returns,” said Michele Telaro, project coordinator on Lesbos for the group Doctors Without Borders.

U.S. Deputy Secretary of State Heather Higginbottom was on Lesbos this week to assess the situation. “There is still a lot of work going on to determine how people will be processed and what that will look like,” she said. “We’re eager to see those details as much as everyone else.”

The Greek parliament passed legislation late Friday designed to ease concerns about whether the human rights of irregular migrants would be protected under international law. The asylum amendment bill stated that people will be sent back to a “safe third country” or a “safe first country of asylum” without explicitly designating Turkey as safe.

Tensions are rising. As disturbances broke out at migrant hot spots on the Greek mainland this week, authorities announced plans to send additional police to the islands to keep order. Activists told reporters that Greek police used stun guns on Syrians and Iraqis on the nearby island of Chios, where fences were torn down in protest.

In the good camp on Lesbos, where the last hundred refugees are waiting for a ferry ride to the Greek mainland, the residents still can dream of making it to the heart of Europe. These asylum seekers were smuggled to the Greek island from Turkey before Europe shut the door to new arrivals on March 20.

The camp is spotless, with fresh herbs growing in flower boxes and a quartet of Greek musicians serenading the residents, who are smothered with help from a dozen humanitarian aid groups.

“We don’t call them ‘refugees.’ They are our guests,” said Stavros Myrogiannis, manager of the Kara Tepe site, correcting a visitor. He seemed sad to see them go.

This is the Europe with open arms, the Europe of 2015.

Myrogiannis estimated that, over the past six months, he has “hosted” hundreds of thousands of “travelers” from war-torn Syria, Iraq and Afghanistan who made the perilous trip across the Aegean Sea.

Asked what he thought when he learned that the people of Lesbos and the other Greek islands were to be nominated for the Nobel Peace Prize for their acts of charity, Myrogiannis waved away the flattery.

“We acted like human beings,” he said. “That is enough.”

One of his last guests was Hasan Zaheda, 31, a landscape designer from Damascus, Syria. He, his wife and toddler son barely made it before the cutoff date. The first raft they were put on by smugglers in Turkey sank, the second trip was foiled by police, the third by foul weather. The fourth was the charm. They were rescued by the Greek Coast Guard.

About 400 people have died in the Aegean Sea crossings this year. Most of them drowned, according to the Greek Coast Guard. An additional 170 are missing and presumed dead.

“We know we are lucky,” Zaheda said.

He said he hopes to live in Paris, where his brother-in-law works at the Pasteur Institute.

A few miles away, at the bad camp, life and prospects for the future are far less sunny. Thousands of migrants are detained behind high fences at a former military base near the village of Moria. The toilets are overwhelmed, the asylum seekers complain, and the food is disgusting now that aid organizations such as Doctors Without Borders and the International Rescue Committee pulled out in protest, refusing to work at what they called a “detention” facility.

This is Europe 2016. These are the migrants who had the misfortune to arrive in Greece after March 19.

“I am living in a prison,” said Mohammad Al Balkhi, 21, a Syrian college student from Damascus, who stood by the fence, amid a pile of cigarette butts, speaking with a reporter before a police patrol shooed his visitor away.

“Get us out of here,” he said. He seemed amazed that the difference of a day or two would determine his fate.

If Europe is to make good on its promise to shut down the deadly smuggling route through the Eastern Mediterranean, which has brought more than a million migrants to the continent, then it will happen here in the islands.

German Chancellor Angela Merkel said uncontrolled illegal mass migration across the Aegean Sea, assisted by rapacious smugglers who put passengers on unseaworthy rafts, must stop. Allowing the migration to continue is not only wrong, it is deadly.

The European Union and Turkey agreed last month that all irregular migrants who arrive in Greece after March 19 will be returned to Turkey.

The E.U.’s Frontex agency, which is responsible for stopping illegal immigration, is bringing 1,500 police officers, asylum case workers and interpreters to Greece to begin processing the migrants.

The ferries will leave Lesbos and head to Dikili on the Turkish coast. Mustafa Nazmi Sezgin, the deputy governor there, said the Turks would erect a temporary transit facility to receive the returnees. “They won’t stay here,” he said. “They will go to other places in Turkey.” He was not sure where.

He agreed that war refugees would be angry to find themselves back in Turkey, but shrugged.

The European Union, including the Greek government, argue that Turkey is a safe haven, proven by the fact that the country already hosts about 3 million Syrian refugees.

As of Friday, there were more than 5,000 migrants on six Greek islands; the largest number, almost 3,000, were on Lesbos. The number of migrants making the trip from Turkey to Greece has plummeted in recent weeks — from thousands a day to hundreds. Aid workers and migrants say the reason was a combination of rough seas and anxiety over what will happen to new arrivals.

Another 46,000 asylum seekers are on the Greek mainland, spread out at more than 40 camps, where the security situation and living conditions are deteriorating.

The mass migration to the heart of Europe was stalled in Greece after Macedonia shut down its border to new arrivals a month ago.

Smugglers in Turkey told The Washington Post that the trafficking cartels were exploring alternative routes to Western Europe through Albania, Bulgaria and Romania. They also warned that smugglers may reopen routes using derelict trawlers and freighters from Libya to Italy, a trade that could incorporate militias operating in Libya, including the Islamic State.

Aid workers said the first people to be sent back to Turkey may likely be the “easy” cases — those deemed immediately inadmissible for asylum in Europe, such as economic migrants from Pakistan, Bangladesh or Nepal.

“Everyone is waiting to see what happens next,” said Panos Navrozidis, country director for the International Rescue Committee. “That’s part of the problem for everyone. Not knowing.”

Read more:

Germany learns how to send back migrants: Pay them

New plan for migrants draws scorn as Germany’s Merkel struggles for unity

7 things to know about the incredibly complicated migrant crisis

Today's coverage from Post correspondents around the world