Named after Jai Singh II, the Jaigarh fort is perched on a cliff surrounded by huge battlements with inside walkways. It is one of the few military structures of medieval India preserved almost intact, containing palaces, a granary, a well-planned cannon foundry, several temples, a tall tower and a giant mounted cannon-the Jain Ban (Jaivan) the largest cannon in the world. Jaigarh Fort also known as the fort of victory, is a rugged structure built in 1726 by Sawai Jai Singh. Situated in the north of Jaipur, this fort is structurally similar to the Amber Fort. The fort stands above the Amber Palace and was never captured and hence is practically intact. The armoury has a large collection of swords and other weapons. There is a watchtower at an elevated part of the fort, offering a panoramic and imposing view of Amber and the neighbouring area. The central courtyard has three enormous underground water tanks, one used by prisoners for bathing, one that was said to hold the gold and jewels and one, which was empty. There are also gardens, a granary, the 10th century temple of Ram Harihar and the 12th century temple of Kal Bhairav.