A UNESCO World Heritage Site, Agra Fort is a massive red sandstone fortress that served as the main residence of the Mughal emperors until 1638. The fort houses several impressive buildings, including the Jahangir Palace, Khas Mahal, and the stunning Diwan-i-Khas. Walking through its grand courtyards and palaces, you can almost hear the echoes of history and the stories of the empire's opulent past.