The largest gathering of snakes in the world happens annually in Manitoba, Canada.
The Narcisse Snake Dens near Winnipeg is home to more than 75,000 red-sided garter snakes, and each spring they attract tourists from all over the world.
National Geographic recently shared video of the dens, which might not be good viewing for everyone.
If you don't like snakes, we'd advise not watching this and checking out some other videos from around our site.
This supplemental article from National Geographic gives more detail, and highlights why the dens are such an ideal spot for the snakes to live. Despite -40 winter temperatures, rural Manitoba's limestone crevices make for warm, underground lairs that are located beneath the frost line.
The garter snakes spend their winters in the crevices, conduct their mating rituals in early spring, and emerge in the summer to feast on the abundant frogs and other food supplies found in the area.
It all adds up to a claim of the largest collection of snakes in the world, and Indiana Jones' worst nightmare.