The Ranikot Fort also known as Dewar-e-Sindh (Great Wall of Sindh), with a circumference of about 26 km or 16 miles, is reputed to be the largest unexplored fort in the world. Its wall is 2nd largest wall after Great Wall of China and made of gypsum and lime cut sandstone, with an average height of 6 meters. Since 1993, it has been on the list of tentative UNESCO World Heritage Sites. It is located in the Kirthar Range, about 30 km southwest of Sann, in Jamshoro District, Sindh, Pakistan.
Ranikot is the most talismanic wonder of Sindh. Visible from five kilometers away its massive undulating walls twist and dip over the hills. Its walls, are built with dressed sandstone and reinforced with 45 bastions along the outer wall, of which 7 are rectangular and the remaining are round. All modified through the ages to accommodate the use of gunpowder, this perhaps makes it the largest fort in the world.