RAFAH, Egypt — They stood just outside the gates of the Rafah crossing on the Egyptian side of the border with Gaza, a couple of inconspicuous Bedouin men waiting for people to be denied entry. As the disappointed travelers retreated, the Bedouins whispered from behind the gates: “You want to go to the tunnels? Fifty dollars.” Their gaze fixed on the Egyptian border police officers, who turn a blind eye to the Bedouins so long as they do not mention the tunnels within earshot.


Technically illegal in Egypt, the tunnels lie at the heart of life and commerce here. Even though Gaza’s border with Egypt was officially reopened for travelers last year, Gaza still depends on the tunnels for most of the basics, like food, building materials and clothes, as well as luxuries like electronics, cars and even wedding dresses.


The underground passageways are concealed in a “tunnel village” that I set out to find. It was not all that hard: on the main road to the Rafah crossing, just turn left at the purple bougainvillea. This road leads through a village of shut doors and few shops. The air is heavy with the sandy dust from the hundreds of excavations; everything melts into a brown haze, so it is difficult to see 25 feet ahead.


Stony tracks lead to clusters of houses shut off from the street by heavy shutters. In time, I negotiated my way into a narrow tunnel lined with heavy wood, whose entrance was hidden in a garden shed.


As I stepped onto three wobbly bricks leading into the tunnel, the first thing I heard was “Watch your head.” This phrase would be repeated many times during the 1,000-foot walk to the Gaza side. After about the 10th warning, I yelled up the tunnel, “I’m much more worried about being bombed than grazing my head!” My guide, who, like the others I spoke with here, refused to give his name for fear of the authorities, guffawed. It took him half a minute to recover from the “ridiculousness” of my concern.


There were four more workers just inside the mouth of the tunnel. As they crouched on the ground, intertwined with the pulley system, the workers transported crushed stones that would be used to make bricks for construction in Gaza. It is a painstaking process. The stones arrive by the ton and have to be loaded by hand into the tunnel, where they are placed in large blue plastic baskets that are connected to form a long train.


Empty baskets whizzed past us and jolted to a stop at the tunnel’s entrance.


“This is our life,” said one of the workers, his face iced in a layer of white dust. “Life is expensive, and Rafah is even more high-priced than Cairo. So we are forced to work and live underground.”


We walked for about 100 yards, and at one point the tunnel opened up wide enough to fit a car. But for the most part we were bent double, and my guide refused to continue until my head was practically at floor level, safely out of danger of being hit (at least from above).


The tunnel is dug only six feet or so below the surface and runs almost exactly straight.


Despite their humble appearance, these tunnels — particularly the newest ones — are built with skill and precision. The wood joints are exact; the lanterns are placed strategically to allow enough light without wasting too much electricity. After hobbling along for about 300 yards, I finally saw the light at the end.


My guide told me to wait while he spoke to the tunnel’s owner.


“You have to have a permit from the Gazan government to cross,” the guide told me. “If you don’t, Hamas will fine him $1,500.”


As I waited for the owner to check that no authorities were around, two women appeared at the entrance to the tunnel. They tiptoed in, and one whispered, “I’m not sure about this” as they disappeared into the seemingly endless tunnel, flipping up their niqabs to breathe more freely.


I was beckoned out of the tunnel, and I met its owner, a Palestinian. A permanent grin etched into his dusty, weathered face, he explained how crossing into Gaza works.


“If anyone wants to cross from Egypt, via my tunnel, he has to call me up about a week in advance, and he needs to apply for a permit with Hamas,” the owner said. “From the Gazan government’s point of view, whether you cross by border or by tunnel, you need permission.”


Many Egyptians believe that, after the revolution that toppled the government last year, the Rafah crossing should be opened up for trade and complete freedom of travel, ending an economic siege on Gaza.


Gazans have always considered the tunnels a legitimate trade and passenger route, one that is necessary for survival in light of the blockade. The Israeli government views the tunnels as an illegal smuggling route and often targets them in airstrikes, which usually trap and kill workers.


Despite the frequent Israeli bombings and, during the era of President Hosni Mubarak in Egypt, deliberate flooding and even electrocutions, the tunnel workers are unfazed by — or perhaps desensitized to — the prospect of a collapse. As I briefly stepped out into Gaza, the tunnel’s owner laughed when my guide told him that I was worried about an airstrike.


Right on cue, an Israeli F-16 roared over our heads, and the owner looked up at the plane with a huge grin and mockingly beckoned its pilots to bomb where I stood. He pointed at me and shouted skyward, “She’s over here!”


Everyone exploded with laughter, and as I turned back and crouched into the tunnel to return to Egypt, the owner called out to me, “Watch your head!”