Agra Fort is an important 16th-century Mughal monument. This powerful fortress of red sandstone encompasses, within its 2.5-km-long enclosure walls, the imperial city of the Mughal rulers. It comprises many fairy-tale palaces, such as the Jahangir Palace and the Khas Mahal; audience halls, such as the Diwan-i-Khas; and two very beautiful mosques.