A large network of spider webs stretching over half a mile is blanketing a Greek lake and surrounding city, making it look like something out of an arachnophobe’s nightmare.

Local photographer Giannis Giannakopoulos recently took to Facebook to share some amazing images of the dense webs, which house hordes of spiders and cover an alarming 0.6 miles of land in Aitoliko, Greece. As the photos show, vegetation, roads, and buildings all over town are draped in the fluffy, white stuff.

The webs are the creation of hundreds of thousands of spiders of the genus Tetragnatha—tiny creatures measuring no larger than 0.7 inches. The water-loving arachnids are common to the area and are often referred to as “stretch spiders” due to their elongated bodies.

A spider from the genus Tetragnatha. Image: Sharp Photography via Wikimedia Commons

While their presence isn’t unusual, locals generally don’t see them in these numbers. Scientists blame the population explosion on high temperatures and humidity coupled with the year’s remarkable mosquito population boom.

“That massive rise has provided ideal and fertile growth conditions for the spiders,” Biologist Efterpi Patetsini told The Daily Mail. “It is a natural development and the web will expand further because of the abundance of food the spiders now have.”

Events of this magnitude are rare, but large webs can sometimes be seen in other areas of the country. Biologists report that the phenomenon occurs every three to five years when the weather becomes unseasonably warm and humid.

While the webs are a bit eerie, the plentiful spiders are not harmful to humans. In fact, their presence is actually beneficial due to the fact that they reduce the mosquito population.

The video below, posted to YouTube by Giannakopoulos, shows the webs blanketing trees along the beach: