Thatta, town, Sindh province, Pakistan, just west of the Indus River, inland from Karāchi and the Arabian Sea coast. During the 16th century it was the capital of the Sammā dynasty in Lower Sindh. Incorporated as a municipality in 1854, it has two mosques (notably Jāma Mosque [1647–49], built by the Mughal emperor Shāh Jahān), historic tombs, and a library. Nearby Makli Hills is a vast necropolis containing thousands of graves. Cotton and silk lungīs (sarongs) are its chief products.
The surrounding region includes the barren and rocky Kohistān area and the swampy deltaic land of the Indus. Sugarcane is the chief crop; camel breeding is significant. Nearby excavations reveal occupations dating from the 1st century bc. Pop. (1998) 36,915.