The largest gathering of snakes in the world woke up from a nap — and the photos are insane

National Geographic/YouTube

Each year at the break of spring, red-sided garter snakes in Narcisse, Canada, engage in an unusual ritual.

Thousands of them begin emerging from their underground dens during the last week of April, and their numbers peak during the second week of May. The reason? They're all out to mate.

Here is what goes down at the snake dens:

Like all other snakes, red-sided garters are cold-blooded. During the winter, when the temperatures drop to below freezing, they hibernate for eight months.

Source: National Geographic

Manitoba, Canada, is laced with sinkholes that line its superficial limestone bedrock. Underground dens form here, attracting the snakes, who see them as the ideal spots for an eight-month snooze.

Source: National Geographic

But space is limited. Thousands of snakes end up in dens as large as an average living room.