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.”