Agra Fort is a massive red sandstone fortress on the banks of the Yamuna River, built by the Mughals as both a military stronghold and imperial residence. Construction began under Emperor Akbar in 1565, and the fort later became the palace complex of Shah Jahan, who was famously held under house arrest here by his son with a distant view of the Taj Mahal he built for his wife.
Highlights inside the fort include the Jahangir Palace, the Khas Mahal, the Diwan-i-Am (Hall of Public Audience), and the Musamman Burj tower, where Shah Jahan is said to have gazed at the Taj Mahal in his final years. Entry is only through the Amar Singh Gate.
The fort is open daily from 6:00 AM to 6:00 PM, with last entry at 5:30 PM. The best time to visit is October through March, ideally in the early morning between 6 and 9 AM, when temperatures are mild and crowds are thinnest.