The importance of crowd control is never clearer than after a stampede, when a mass of people, usually driven into a panic by something, rushes toward something else. A large throng in a tight space, with little room to move, can quickly take on a life of its own, as history has demonstrated time after time. As one author describing the Bethnal Green Tube diaster in 1943 explains, "Stampedes start in the wild when animals, guided by herd-instinct, bolt away from perceived danger towards perceived safety. People, despite being supposedly more rational beings, join stampedes for the same reason. It is not so often the stampede that kills, but the resulting crush."
Some of the worst stampedes in history have taken place during the Hajj, the annual Muslim holy time when pilgrims are meant to make their way to Mecca. The huge crowds often overwhelm local structures like bridges and tunnels. When fears and rumors start to make their way through the mass of humanity, tragedy often follows. The 2015 stampede in Mina, Saudi Arabia, is an example of this, with too many people in too small a space, all moving too quickly. But disasters in Saudi Arabia are far from the only times crowds have panicked and trampled each other. Soccer games, festivals, holidays, nightclubs, and theaters have all seen stampedes, usually due to poor security, lack of regulation, and the human tendency to try to go back through the same entrance door in which they arrived.
Because of the tragedies on this list, safety regulations in the United States are now some of the toughest in the world, but this wasn't always the case.