One of the few ancient Indian military structures to be kept intact through the ages, Jaigarh Fort has recently been opened to the public. It was sealed for seven years, due to a rumour, that an enormous treasure in gold was buried, in the fort area. The fort houses several palaces, gardens, a granary, an armoury, temples, and most significantly the Jai Ban, the largest antique canon, in the country. 

It is within walking distance of Amber, and offers a fantastic panaromic view of the surrounding plains, from the Diwa Burj watchtower. 

For detailed information on how to reach there and where to stay, see Jaipur.