“During World War II, when the people in the surroundings were informed that planes carrying bombs were arriving, they would take shelter in the first chamber of this tunnel. „It’s called an air-raid shelter,” the man explains and points at Emil’s toy. “Do you know the name of those planes?”

“Bombers!” he exclaims.

“Exactly! During World War II, B-17 bombers were flying over Luxembourg. The miners could hear the roar of the engines even underground. Two of those bombers actually collided and crashed nearby. Today, a small museum in Perlé commemorates that event.”

“Perlé… is that far away?” I ask.

“It’s not far,” he replies. “You can walk there. That’s what the Leekëpperten, the people who worked here, used to do too."

Then the moment finally arrives: we descend a steep staircase into the depths of the “Johanna” tunnel. Luckily, we’re wearing sturdy shoes because countless steps lead us 42 meters underground. Water drips from the ceiling, and our footsteps echo. Once we reach the bottom, it’s totally silent. Only the sound of dripping water can be heard.

“The miners used to work down here,” explains the tour guide while he shines his lamp on the walls.

I carefully run my hand over the rock. “So this is slate…”

“Exactly,” he says. “The men used to have to remove the stone out of the mountain with tools—without any machines at all.”

Emil looks around. “It’s really dark and huge down here…”

The man nods. “Imagine being down here all day. With just a small lamp.”

We don’t even want to imagine that. How exhausting this work must have been. We continue from one fascinating chamber to the next and marvel at the huge underground lake. When we finally climb back up, the daylight blinds us.

“Now let’s go to Perlé!” Emil calls out. In front of the museum, a path leads up to the next village, and we set off on our next adventure.