From the terrace near the Police Museum you can look down into the narrow entrance where 470 Mamluk beys (governors) were killed by Mohammed Ali's troops in 1811, thus ending Mamluk influence in Egypt and consolidating his rule. The Mamluks had been summoned to the citadel for a celebration but once they had entered, the gates were shut, trapping them in the defile and allowing troops loyal to Mohammed Ali to easily slaughter them.