Ranikot Fort is also known as The Great Wall of Sindh and is believed to be the world's largest fort with a circumference of approximately 26 kilometres. Since 1993, it has been on the tentative list of UNESCO World Heritage Sites.The original purpose and architects of Ranikot Fort are unknown. Archaeologists point to 17th century as its time of its first construction but now Sindh archaeologists agree that some of the present structure was reconstructed by Mir Karam Ali Khan Talpur and his brother Mir Murad Ali in 1812 at a cost of 1.2 million rupees (Sindh Gazetteer, 677).