Researchers have discovered a vast spider “megacity” inside Sulfur Cave, a cavern on the Albania-Greece border, according to the journal Subterranean Biology.
The colony, spanning nearly 110 square meters, is home to about 69,000 Tegenaria domestica and 42,000 Prinerigone vagans spiders living in a single interconnected web.
Scientists say the web could be the largest of its kind ever recorded, thriving in a dark, humid ecosystem.
The footage was filmed by István Urák, with photographs by Czech cave explorer Marek Audy.