years, completing it in 1573. It was only during the reign of Akbar's grandson, Shah Jahan, that the site took on its current state. Shah Jahan built the beautiful Taj Mahal in the memory of his wife, Mumtaz Mahal. Unlike his grandfather, Shah Jahan tended to have buildings made from white marble. The fort was under the Jat rulers of Bharatpur for 13 years. In the fort, they built the 'Ratan Singh ki Haveli'. The fort was invaded and captured by the Maratha Empire in the early 18th century. Thereafter, it changed hands between the Marathas and their foes many times. After their catastrophic defeat at Third Battle of Panipat by Ahmad Shah Abdali in 1761, Marathas remained out of the region for the next decade. Finally Mahadji Shinde took the fort in 1785. It was lost by the Marathas to the British during the Second Anglo-Maratha War in 1803. The fort was the site of a battle during the Indian rebellion of 1857 which caused the end of the British East India Company's rule in India and led to a century of direct rule in India by Britain. On 30 November 1871, thirty six people died when a cartridge factory located inside the fort exploded. Layout The fort has a semicircular plan, its chord lies parallel to the river Yamuna and its walls are seventy feet high. Double ramparts have massive circular bastions at intervals, with battlements, embrasures, machicolations and string courses. Four gates were provided on its four sides, one Khizri gate opening on to the river. Two of the fort's gates are notable: the "Delhi Gate" and the "Lahore Gate." The Lahore Gate is also popularly also known as the "Amar Singh Gate," for Amar Singh Rathore. The monumental Delhi Gate, which faces the city on the western side of the fort, is considered the grandest of the four gates and a masterpiece of Akbar's time. It was built circa 1568 both to enhance security and as the king's formal gate, and includes features related to both. It is embellished with intricate inlay work in white marble. A wooden drawbridge was used to cross the moat and reach the gate from the mainland; inside, an inner gateway called Hathi Pol ("Elephant Gate") – guarded by two life-sized stone elephants with their riders – added another layer of security. The drawbridge, slight ascent, and 90-degree turn between the