If you are visiting Jaigarh fort in Jaipur you are sure to see Jaivana, believed to be the biggest cannon in the world. It was cast by Maharaja Jaisingh II in 1720. Jai Singh II took a keen interest in developing armory and munitions. Perhaps he also wanted to impress his Mughal overlords. The gigantic proportion of the gun is quite impressive. It is 20 feet long and weighs 50 tonnes. But the size and weight itself would have been a weakness. It was (test) fired only once. Folklore has it that the 50 kg cannonball traveled 45 kms. Ballistics experts reckon that it would not have been more than 5 kms. Definitely worth ticking the box if you visit Jaigarh.