These are the ways a Syrian gets into Turkey: Legally, with a passport. Bleeding, in an ambulance. Or without papers, in a heart-pounding dash at night through a field of cucumbers, as Turkish border guards shout curses and fire shots in the air and smugglers shove their clients through a gap in the barbed wire fence, hissing “Hurry, hurry, hurry.”

Or the fleeing Syrians can wait their turn — for months — to get into a refugee camp.

More than 120,000 Syrian refugees are now in Turkey, straining the nation’s hospitality. The Turkish government cannot build refugee camps fast enough, and so tens of thousands of Syrians are backed up on the Syrian side of the border, where families have been camping under the stingy shade of olive trees, without tents, in the dirt with their sad pots and pans.

In recent weeks, the Turkish government has made illegal crossings from Syria much more difficult. In the past, Turkish soldiers might turn a blind eye, especially for refugees, and a few dollars. They are now aggressively enforcing the country’s borders. Government officials say they are worried the frontier with Syria has become too porous, too wild — an open turnstile of hashish, stolen cars, weapons, cash and militant jihadis.

In a small farming village a few miles away on the Turkish side of the border, near the city of Reyhanli, the rooftop terrace of a local smuggler’s house at sunset begins to resemble a crowded transit lounge, filled with army deserters and money couriers, the haggard clients smoking cigarettes and waiting their turn to hear that the border guards have passed, and that it is okay to make a run for it.

“Before the Turkish soldiers showed pity, but no more,” said a Syrian teacher who was waiting to cross into Syria to pick up a wounded fighter and bring him back to a rebel convalescence hospital in Turkey.

As the teacher and other clients waited, the smuggler, a Mr. Big in the area, answered dozens of rings on his cellular phone, from his eyes and ears along the fence line. He made $20 or $30 from anyone he could get across.

Later, as the teacher sprinted toward the barbed wire frontier, he was quickly surrounded and stopped by Turkish soldiers, who smacked his traveling companion hard in the chest.

“Look! They’ve been caught!” said an old man with a cane sitting on the terrace, who was watching the game of cat and mouse as an evening’s entertainment.

The next morning, a middle-class Syrian man who had to return home to get his family ventured across. He and his guides were driven a few miles down the fence line, to a muddy olive grove, where he slipped and slid into the muck of irrigation canals and began to panic.

Farmers in the field were whistling and yelling — the soldiers are here, they are there — and finally the client was asked for an extra $15 to bribe a Turkish soldier to pass. Whether money went to the farmers or the solider is uncertain. But after the man passed under the fence, the soldier fired off a round into the air.

On the Syrian side, in the village of Atmeh, refugees fill two schoolyards, a mosque, several olive processing factories and a farm. “We have 4500 under our care, and a few thousand more staying in our homes,” said Abu Abdu, a former chef who now dons pressed camouflaged fatigues and answered his cellphone with a barking “How many more?”

“Maybe 500 leave us in a day,” Abdu said. “But a thousand new refugees come.” Some go to Turkey, legally, as refugees, others sneak across and many appear to just wait. He said the town was being overwhelmed.

As he spoke, one family after another arrived at a school, piled into the beds of pickup trucks, telling stories of villages bombed.

The refugees are given a blanket, a bar of soap and space in the schoolyard. Very little international humanitarian aid has reached the Syrian side of the border.

A few miles away, thousands of others lay sprawled in an olive grove. Sitting on a straw mat, swatting flies, an older, patriarchal figure who called himself Abu Ibrahim said, “We’ve been here 26 days.”

The extended family was gathered under a tree. They are waiting for a spot in a Turkish refugee camp to open. “Welcome to our home,” he said. There are too few tents, so they live under the sky. The old man pulled a grandchild to his lap and showed a visitor her red eyes. “She’s sick,” he said. Another family member held up his arm and pointed toward recent entry and exit wounds. He tried to wiggle his fingers. “No move,” he said in English.

In the evening, at the edge of the Syrian camp in the olive grove, the smugglers turned off the lights on their motorbikes and quietly drifted to a stop into the fields, their clients mounted on back.

Suddenly, a cadre of Free Syrian Army fighters rolled up and demanded to know who was who. The fighters explained they were trying to control the hash traffickers, who they felt were taking advantage of the border chaos — prompting the Turkish government to tighten security and, in turn, making it harder for refugees to cross.

A young smuggler wearing skinny jeans, a philosophy major in college, from a good family in Atmeh, led a group through the fence as searchlights from Turkish patrols leapt across the fields.

Asked the secret of his success as a smuggler, the philosopher said, “Run fast.”