Constantinople was one of the most heavily fortified cities in the world. When it was attacked on April 6, 1453, 10,000 men easily held off Sultan Mehmed II’s 100,000-150,000 attackers for fifty days. The Ottoman Turks used every weapon at their disposal in their attack, including massive cannons and a sea blockade. What ultimately brought the great city down wasn’t high-tech weapons or brilliant military strategy; it was an unlocked door.

The attackers tried their best to conquer the city. In one attack, they started with heavy artillery bombardment before storming the weakest points on the walls. After two hours, the defenders forced the attackers into retreat.

Another attack used the powerful cannons to punch a hole through the gates. Using this point of entry, the invading forces poured into the city, but were massacred by the residents of Constantinople, who easily took out each soldier as he entered through the breach.

Just when it looked as if there was no way to successfully enter the city, someone happened to notice the Karoporta Gate had been accidentally left unlocked. The invading forces flooded into the city on May 28. Although this onslaught was finally fought off, it required diverting defenses from other vital points. Consequently, the invading Ottoman Turks were able to penetrate the city at a number of other locations, resulting in the fall of the city.

In the chaos and carnage of the attack, history somehow lost any record of what happened to the guy who just had one job: lock the stupid gate.

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