ATMA, Syria -- From a distance, the tents look like an unfurled streamer, a wave of white filling the olive grove and crawling up the barren hillside on the Syrian-Turkish border, almost a work of environmental art.

This is Syria’s biggest camp for the internally displaced, and the flimsy tents shelter more than 20,000 people who have nowhere else to go.

In its poverty and dire shortages, its poor hygiene and lack of utilities, Atma’s white wave has become a symbol of the plight of the hundreds of thousands of Syrians who’ve fled the fighting in their country.

The United States has deferred to the United Nations in distributing food and other aid to Syria’s displaced, but the U.N. won’t enter any part of Syria without the government’s permission. That’s even more ironic here because Atma is directly across the border from Turkey, with no checkpoints or roadblocks. Yet U.N. agencies haven’t come even for an inspection.

“We know about Atma,” said Amanda Pitt, a spokeswoman for the Office for the Coordination of Humanitarian Affairs, a little-known U.N. agency. “In order to get to these parts of northern Syria you have to cross the border,” she told McClatchy on Wednesday. “We have to work with the government of Syria in order to cross the border.”

Three hundred or more civilians, often with only the clothes on their back, drive up the winding, rutted road every day, traveling in the cargo bays of open trucks, which they hire for the trip. Then comes the letdown: There are no more tents, and the only place to sleep is in the small mosque.

Khairiah Hallakh, 28, arrived here last week with her family from Qastoun in Hama province, a village of 2,000 that troops loyal to President Bashar Assad have been bombarding with artillery and rocket fire as part of a little-reported government offensive to seize control of the Sahel al Ghab valley, where rebels move about freely.

“We fled because of the shelling. And after we left the house, a rocket hit it,” she recounted. “We didn’t even bring blankets. We picked up our children and fled,” she said. She said that 1,000 people from Qastoun were here.

Atma jars the senses of any visitor. Syrian jets routinely fly over it or the nearby villages, scaring everyone inside; they fear a repeat of a November incident, when jets reportedly bombed a nearby camp at the Bab al Hawa border crossing. The Atma clinic is in chaos: unheated, unlighted and with a threadbare supply of medicine and equipment. But the most surprising fact here is the near-complete absence of the international community.

Atma, which was set up with the help of Saudi money, is in humanitarian limbo, and no foreign government or international aid organization has taken responsibility for it, not nongovernmental charities and not the International Committee of the Red Cross.

Aid agency representatives say that’s because they’re distributing aid in areas that are under the government’s control and offering aid here without the approval of the Syrian government risks their programs elsewhere.

“We cannot do cross-border operations,” said Abeer Etefa of the World Food Program, a U.N. agency that’s charged with feeding those in such dire straits as people in the Atma camp. “We do not have the permission to go across the border from Turkey to deliver aid. Our only mode of sending is to go from inside Syria, from our warehouses in Damascus.”