Carnival of Binche is what art school students' design roommates have nightmares about.
Dating back to the 14th century, the carnival of Binche takes place each year during the Sunday, Monday and Tuesday before Ash Wednesday. During those days, Binche's streets fill with performers dancing, playing music and marching. Much of the city gets into costume purportedly to celebrate the occasion, but seemingly to scare the living daylights out of visitors.
If travelers weren't coulrophobic before heading to Binche, there's a chance they'll have a healthy fear of clowns after coming across some of the hundreds of makeup-slathered "Gilles" cavorting in the streets. Dressed like rejected members of Anonymous in court jester garb, the Gilles' faces are obscured by Guy Fawkes-style wax masks and tanning booth glasses. They pound drums and wield sticks to ward off evil spirits, wear large hats of ostrich feathers and march through town with baskets of oranges that they whip at members of the crowd with such velocity that townspeople cover the windows around this time of year.
Being a Gille is a big deal in Binche, so running away screaming or lobbing an apple in response is discouraged. Unesco has named Binche's Carnival celebration an essential part of the world's oral and intangible heritage, though, so it's worth sticking around to see what the scary men in masks will do next. Let's put it this way: If you're good with a grown man in a mascot costume launching a T-shirt at you through a pneumatic gun, you should fare just fine with the Gilles of Binche.