Strange Crazes

On July 14, 1518, a woman known as Frau Troffea stepped into a narrow street in Strasbourg and started dancing in total silence. She didn't stop. She danced for almost a week until she collapsed from sheer exhaustion, kicking off one of the strangest medical events in history.

Frau Troffea wasn't faking it. She was suffering from mass psychogenic illness—a bizarre condition where severe stress makes the brain trigger real, involuntary physical symptoms. Because human brains are wired to mimic others, her neighbors subconsciously caught the bug. Soon, dozens of exhausted people were shuffling and leaping through the streets.

By August, the crowd of involuntary dancers had swelled to nearly 400. Desperate to stop the chaos, city officials decided the best medical cure was for everyone to just "dance it out." When their ridiculous solution backfired, authorities finally banned public dancing, and the exhausted citizens slowly stopped twitching by September.

###Dutch Tulip Mania

The Netherlands, 1636–1637 — For a few wild months, wealthy Dutch merchants completely lost their minds over fancy flower bulbs.

In the early 1630s, wealthy merchants in the Netherlands developed an obsession with a newly imported luxury: the exotic tulip. They specifically prized rare bulbs with brilliant, flame-like patterns. Soon, simply growing them wasn't enough—traders wanted to get rich.

By late 1636, a buying frenzy erupted. About 300 to 400 wealthy merchants gathered in crowded taverns to buy and sell tulips on paper contracts. The market moved so fast that a single bulb could be traded multiple times a day, causing prices to increase tenfold by January.

The bubble violently popped in early February 1637. At a routine auction, buyers suddenly refused to pay the outrageously inflated prices. The entire market collapsed overnight. Sellers were instantly left holding worthless paper contracts, bringing an abrupt end to the flower fad.

###The Flagpole Sitting Craze

United States, 1924 to 1930 — In the 1920s, thrill-seekers spent weeks living on tiny platforms hundreds of feet in the air just to set records.

In January 1924, a stuntman named Alvin "Shipwreck" Kelly climbed a flagpole outside a Philadelphia department store. Hoping to drum up some publicity, he perched on a tiny platform for 13 hours and 13 minutes. Instead of rolling their eyes, the American public decided this was an excellent idea.

A bizarre national competition kicked off. Teenagers and adults alike scrambled up poles to break endurance records. Kelly became a superstar, touring 28 cities and charging admission to watch him sit. Whenever a challenger broke his record, Kelly just climbed back up to reclaim his title.

The fad reached its peak in 1930 when Kelly survived for a staggering 49 days atop a 225-foot pole in Atlantic City. Shortly after, the Great Depression hit, and the public's appetite for watching people sit on sticks finally vanished.

###The Tanganyika Laughter Epidemic

Tanganyika, 1962 to 1963 — A stress-driven chain reaction of uncontrollable laughing and crying forced authorities to shut down schools across the country.

On January 30, 1962, three students at a highly disciplined mission-run boarding school in Tanganyika suddenly fell into fits of uncontrollable laughing and crying. The girls weren't faking. They were experiencing mass psychogenic illness, a bizarre medical chain reaction where severe psychological stress causes real physical symptoms.

Because humans naturally mimic each other, witnessing the distress caused a domino effect. The nervous laughter spread to 95 students, forcing the Kashasha Girls' Middle School to shut its doors in March. Hoping to stop the outbreak, officials sent the girls back to their home villages.

It was a massive mistake. The students accidentally carried the contagious anxiety home, sparking identical outbreaks of laughing, crying, and fainting in neighboring communities. The epidemic raged in intermittent waves for 18 months before the collective stress finally faded away and the laughter stopped.

###The Pet Rock Craze

United States, 1975–1976 — A struggling copywriter became a millionaire simply by packing ordinary beach stones into cardboard boxes and selling them as pets.

In 1975, advertising copywriter Gary Dahl was struggling with bills when he joked to friends that the perfect, mess-free pet was a plain old rock. Instead of leaving it as a joke, Dahl bought a massive load of smooth Mexican beach stones for exactly a penny each.

He placed each stone on a bed of straw inside a cardboard pet carrier complete with air holes. The true genius was his hilarious 32-page training manual, which taught owners how to make their new rock "sit" or "play dead." Dahl launched his gag gift at a San Francisco trade show.

Buyers fully understood the rocks weren't alive, but they happily paid $3.95 just to be in on the joke. The fad exploded through the holiday season before fizzling out by February 1976, leaving stores with tons of unsold stones and making Dahl a very rich man.

###The Pokémon Go Central Park Stampede

Central Park, New York City, 2016 — Hundreds of people sprinted blindly through Central Park late at night just to catch a rare digital monster on their phones.

In July 2016, a new augmented-reality mobile game called Pokémon Go had millions of people glued to their screens. Players walked through the real world tracking digital monsters using their phone's GPS. But human crowd-following instincts soon took over.

Late one night, a highly rare digital creature known as a "Vaporeon" spawned inside New York City's Central Park. Word of the monster instantly exploded across social media, alerting nearby players.

What followed was a literal stampede. Hundreds of gamers sprinted blindly through the park in the dark, desperate to catch the digital prize. It wasn't a violent riot, but a bizarre case of extreme, gamified tunnel vision.