After a section of a large industrial tunnel caved in on Wednesday, more than two dozen construction workers who were hundreds of feet beneath the streets of Los Angeles raced for miles in the dark. Remarkably,

The workers on Wednesday night were 400 feet underground and near the coast, as much as 6 miles away from the only entrance.

Workers were 400 feet (121 meters) underground and as much as 6 miles (9.6 kilometers) inside from the only entrance when the cave-in Wednesday evening threatened to trap them on the far side of the tunnel’s boring machine,