Huge Annual Human Gathering

One in every four people on Earth identifies as Muslim. According to Islamic tradition, each Muslim is required to visit the city of Mecca at least once during their lifetime, specifically during the Islamic month of Dhu al-Hijjah, for the Hajj pilgrimage.

Upon arrival in Mecca, pilgrims are required to wear all-white clothing as a way of equalizing everyone in the eyes of God while in Mecca. The centerpiece of the pilgrimage is the Ka’ba, a black cube located at the center of the square, around which pilgrims must walk seven times. Only Muslims are allowed in Mecca and, therefore, in the Hajj, although many non-Muslims have attempted to sneak in throughout history and report their experiences.

The logistics of accommodating an additional two million people in Mecca for one week is a major challenge. One extreme example of this is the Al Mashaaer Al Mugaddassah Metro line, which was designed to help pilgrims move between holy sites during the week of the Hajj. It is a metro line designed to operate for only seven days each year when it becomes one of the world's highest-capacity metro lines.

There is something special about the energy that many people together in one place can generate, whether it be at a religious event, a concert, or a sports event. It is a unique phenomenon that humans can derive energy from crowds, which can drive innovation to allow for more of these events to take place.

Craving more? Check out the source behind this Brain Snack!