A cave scientist studies the giant spiderweb.
© Marek Audy
World’s Widest Web
It’s silky, spongy, and soft. And it’s many people’s worst nightmare! Last October, scientists announced that they had found the biggest spiderweb in the world. It’s in Sulfur Cave, a pitch-black cave at the border of Albania and Greece, two countries in Europe.
The web stretches about 1,140 square feet, making it bigger than most classrooms. The thick, carpet-like web is home to roughly 110,000 spiders.
“It looks like Halloween,” says Serban Sarbu, a scientist who has studied the cave.
Urak et al./Subterranean Biology/Cover Images via AP Images
An estimated 69,000 barn funnel weaver spiders live in Sulfur Cave.
Life Without Light
Jim McMahon/Mapman®
Scientists discovered Sulfur Cave in 2022. They noticed that its gigantic web was spun by two spider species, barn funnel weavers and sheet weavers. Normally, barn funnel weavers prey on the smaller sheet weavers. But in Sulfur Cave, the larger spiders don’t have to depend on their smaller cousins for their next meal. That’s because the cave is filled with countless flies that get caught in the gigantic web, giving the spiders plenty to feast on.
“You can imagine they’re eating about a wheelbarrow full of food each day,” Sarbu says.
The cave is also home to other creepy creatures, including centipedes, scorpions, and bats. It’s rare for a dark cave to be teeming with life. What makes Sulfur Cave special is hydrogen sulfide—a gas that smells like rotten eggs. That stinky gas enables tiny organisms called microbes to survive. They become food for the flies that the spiders end up eating.
Sarbu says he’s glad the cave has gotten so much attention.
“People usually scream when they see one spider,” he says. “It’s fascinating that people have gotten excited about this huge spiderweb.”
