Originally the royal treasury, this dramatic-looking fort has large water tanks for storing rainwater that's been channeled down the hill from imposing Nahargarh. There are fantastic views of Jaipur from the watchtower. Star attraction of the fort is the Jaivana Tope, the largest wheeled cannon in the world, measuring over 20 feet long and weighing in at around 50 tons. The mighty Jaivana was unsurpassed for power in its day; one of its cannon balls was found 35 km (22 miles) from here. This fort was responsible for the defence of Amer Fort (which is at a lower elevation) and its armory and museum showcases the weaponry it once had as well as photographs. Local lore has it that when Indian prime minister Indira Gandhi ordered a search of the water tanks in 1976 a vast collection of gems and jewelry emerged. Guides are available at the entrance—an English-speaking one will charge about Rs. 100. For a small fee you can enter the fort and reach the top (where the cannon is) by car and save yourself a long, uphill walk. It's possible to drive from Jaigarh to Amber, but be sure to get a driver who knows the way through the narrow lanes.